diff --git a/docs/i18n-translation-guidelines.md b/docs/i18n-translation-guidelines.md
index 568465ca..843a0a7a 100644
--- a/docs/i18n-translation-guidelines.md
+++ b/docs/i18n-translation-guidelines.md
@@ -151,6 +151,12 @@ Locales: `en`, `zh-CN`, `zh-TW`, `ja`, `ko`, `fr`, `de`, `es`, `ru`, `he` (RTL).
 > nothing is tracked for alerts). Register follows each file's existing norm: 你 (zh-CN),
 > 您 (zh-TW), Sie (de), tú (es), вы (ru). No remaining `[TODO: Translate]` placeholders.
 
+> **Status (2026-10, scoped scan):** the Refresh dropdown gained a per-root scope section
+> (`loras.controls.refresh.scopeSection` / `.rootOffline` / `.rootModels`) and the scan result
+> toasts (`toast.api.refreshCompleteScoped`, `.refreshKeptUnreachable`, `.scanRootUnreachable`),
+> 6 keys in total. They are `[TODO: Translate]` placeholders in the other 9 locales for now —
+> the feature owner has not asked for this pass yet.
+
 > **Status (2026-10, reconcile walk progress):** a regular Refresh now reports the reconcile
 > walk per model root (which roots are being checked, how many model files have been seen, and
 > an ETA) and splits the progress bar into walk (0-50 %) and new-file (50-99 %) phases, which
diff --git a/docs/plans/issue-1108-scoped-scan.md b/docs/plans/issue-1108-scoped-scan.md
new file mode 100644
index 00000000..c121045f
--- /dev/null
+++ b/docs/plans/issue-1108-scoped-scan.md
@@ -0,0 +1,283 @@
+# Plan: Scoped Scan (one root / one folder at a time)
+
+**Issue:** [#1108](https://github.com/willmiao/ComfyUI-Lora-Manager/issues/1108) — scan a single
+folder/root instead of the whole library.
+**Status:** **P1 implemented** (2026-10-07, uncommitted working tree). P2 (folder scope, Wave 5)
+is not implemented. Supersedes the earlier draft's per-root *status panel* and persisted
+*unreachable-subtree* state (both dropped, see "Must NOT have").
+
+Implementation notes / deviations from the draft below:
+
+* The scope dataclass is public (`ReconcileScope`) because it crosses the scanner → service →
+  route boundary; the draft called it `_ReconcileScope`.
+* `_reconcile_cache()` now returns a summary dict, exposed as
+  `ModelScanner.last_reconcile_summary` and returned by `BaseModelService.scan_models()`, so the
+  scan HTTP response carries the counts (the WS `completed` payload carries the same fields).
+* Root labels are computed over the **whole configured set** and passed into the walk tracker, so
+  the progress line and the menu never disagree.
+* Discovery: `Config._dedupe_existing_paths()` drops roots that do not exist **at config load**, so
+  a drive that is already off when LM starts is not in `get_model_roots()` at all. Two consequences:
+  it cannot appear in the refresh menu (nothing to select), and its cached entries are kept because
+  they are outside every configured root prefix. The `root_unreachable` path therefore covers the
+  *mid-session* case (drive switched off while LM runs), which is the workflow that motivated the
+  issue; both paths keep the entries, which is what matters.
+* Known limitation to keep in mind: after a scoped scan (or one with unreadable paths) the recorded
+  empty-folder list is unioned instead of replaced, so an empty folder deleted on disk can linger in
+  the sidebar until the next full refresh. Models are unaffected.
+
+## TL;DR (For humans)
+
+**What you'll get:** the Refresh ▾ menu can scan **one model root** (one drive) and leave every
+other root untouched. Refreshing while a drive is switched off no longer deletes that drive's
+models from the cache/DB — they are kept and reported. Browsing the grid while a drive is off no
+longer silently strips `preview_url` from that drive's models.
+
+**Why this approach:** a scan scope is a **path scope**, not a device scope, so it also works for
+layouts where one root contains symlinks to other drives. The safety net collapses into one rule —
+*anything this walk could not read is left untouched* — and that rule is nearly free: the root
+existence check already exists, `os.walk(onerror=...)` only fires on failure, and the cached-entry
+prefix attribution is already computed for the walk-progress weights.
+
+**What it will NOT do:** no active probing of nested symlinks; no persisted "unreachable subtree"
+table; no per-card offline badges (separate change); no root enable/disable switch; the main
+Refresh button keeps meaning "scan everything"; no configuration-convention/documentation push to
+re-layout libraries that use cross-drive symlinks (dropped by request).
+
+**Effort:** Medium (~1.5–2 days for P1 including tests)
+**Risk:** Medium-low — the risk sits in the folder-tree (`all_folders`) merge under a scoped scan
+and in the exact pruning predicate; both get explicit tests.
+
+**Decisions to sanity-check:**
+1. A full Refresh now treats a *configured but unreachable* root as "keep + report" instead of
+   "everything under it was deleted". This is a behaviour change (release-note it).
+2. Keep the near-zero-cost **first-level symlink** reachability check (reuses
+   `config._path_mappings`); nested symlinks stay uncovered.
+3. Root labels become set-aware (`G: loras` / `usb/loras`, auto-deduped by parent segments).
+   This also changes the walk-progress line.
+
+## Scope
+
+### Must have (P1)
+
+- **Scope-aware reconcile**: `_reconcile_cache(scope=...)` where scope is
+  `{roots: [path] | None, folder: rel | None}`. Files inside the scope reconcile normally
+  (add / repair / remove); everything outside is neither re-read nor removed.
+- **Path-level pruning guard**: cached entries under a path this walk could not read are excluded
+  from `missing` and reported. Three sources:
+  - configured root that fails the reachability check (already filtered at
+    `model_scanner.py:1468`),
+  - directories `os.walk` failed to enter (`onerror` collector; covers Windows junctions to an
+    offline drive, permission errors, I/O errors),
+  - first-level symlink mappings whose target is not a directory (`config._path_mappings`).
+- **Folder tree correctness under scope**: `all_folders` becomes
+  `(old outside scope) ∪ (old under unreachable paths) ∪ (discovered)`, so a scoped scan cannot
+  collapse the sidebar tree and an offline root keeps its folders.
+- **Result payload** for the toast: `added`, `removed`, `repaired`, `scanned_roots` (labels),
+  `skipped_roots` (`{path, label, kept}`), `unavailable_paths` (`{path, kept}`, capped),
+  `kept_unreachable`.
+- **API**: `GET /api/lm/{prefix}/scan?full_rebuild=false&roots=<path>` (repeatable);
+  `GET /api/lm/{prefix}/roots` gains `root_details: [{path, label, reachable, models}]` while
+  keeping `roots: [str]` unchanged (other callers depend on it).
+- **Frontend**: Refresh ▾ menu lists the current page's roots (label + model count, offline rows
+  greyed out and non-clickable), main button unchanged, root items disabled while a scan runs;
+  scoped completion toast reports counts and any kept/skipped paths.
+- **Preview fix**: a preview 404 must not clear `preview_url` when the file's parent directory is
+  itself unreachable (`preview_handlers.py:57` + `_cleanup_stale_preview_url`).
+- **Set-aware root labels** (`_root_display_labels(roots)`), shared by the progress broadcasts and
+  `/roots`: last path segment, Windows drive prefix (`G: loras`), deduped by prepending real parent
+  segments (`usb/loras`, `a/models/loras`), `(2)` fallback by sorted path, 40-char cap, full path in
+  the tooltip.
+- i18n keys in `locales/en.json` + `python scripts/sync_translation_keys.py`.
+- pytest + vitest coverage for every item above.
+
+### Must have (P2, optional follow-up)
+
+- `folder=<rel>` parameter: walk `<root>/<rel>` for every reachable root that contains it (the
+  sidebar's unified tree has no root identity, so "this folder" means "this relative path in all
+  roots"), prune only inside that prefix.
+- Sidebar folder context menu entry "Scan this folder" (`templates/components/context_menu.html`
+  `#sidebarFolderContextMenu`, above `check-folder-updates`; update
+  `tests/frontend/regression/sidebarFolderContextMenu.test.js` expectations).
+
+### Must NOT have (guardrails)
+
+- NO per-entry symlink probing during the walk — `DirEntry.is_symlink()` costs a syscall per entry
+  on Windows, the exact cost the reconcile optimisation removed. Nested symlinks stay uncovered.
+- NO persisted `unavailable_paths` table, no DB schema change, no new cache state.
+- NO configuration-convention guidance for cross-drive symlinks (dropped by request).
+- NO per-card/modal offline badges in this plan (separate change; needs the L1 prefix list which
+  P1 produces, so it can build on this later).
+- NO root enable/disable setting, NO status panel in Settings.
+- NO change to `full_rebuild=true` (it still walks everything and replaces the cache);
+  `roots` + `full_rebuild=true` is rejected with 400.
+- NO new dependency, NO change to the extension-facing endpoints.
+- NO `os.path.realpath` for scope/prune routing — business paths only (AGENTS.md rule).
+
+## Todos
+
+### Wave 1 — backend semantics and safety net
+
+1. **Scope plumbing in the scanner.**
+   What to do: add `_ReconcileScope` (dataclass: `roots: Optional[List[str]]`, `folder: Optional[str]`)
+   and `_reconcile_cache(scope=None)`. Resolve the effective root list once: configured roots ∩
+   scope.roots, filtered by reachability; missing ones become `skipped_roots` (never pruned).
+   `_walk_roots_for_reconcile` / `_walk_root_group_sync` / `_walk_root_for_reconcile` take the scope
+   so the walk can start at `<root>/<folder>` while still computing `folder`/`file_path` relative to
+   the **root** (`_process_model_file(path, root_path)` must keep receiving the root).
+   References: `py/services/model_scanner.py:1453` (`_reconcile_cache`), `:1468` (root filter),
+   `:1832` (`_walk_root_group_sync`), `:365` (`_walk_root_for_reconcile`), `:134`
+   (`_count_cached_entries_per_root`), `:126` (`_normalized_root_prefix`).
+   Done when: a scoped reconcile over 2 roots leaves the other root's `raw_data`, hash index and
+   folder list byte-identical.
+
+2. **Pruning predicate + unreachable collection.**
+   What to do: `missing = {p for p in cached_paths - found_paths if in_scope(p) and not
+   under_unreachable(p)}`; collect unreachable prefixes from (a) skipped roots, (b) an `onerror`
+   callback on `os.walk` (record `oserror.filename` as a business path), (c) `config._path_mappings`
+   entries whose target fails `os.path.isdir` (mapping is keyed target→link; protect the **link**
+   prefix). Count the kept entries per prefix for reporting.
+   References: `py/services/model_scanner.py:1679` (`missing_files = cached_paths - found_paths`),
+   `:398` (`os.walk(..., followlinks=True)`), `py/config.py:167` (`_path_mappings`),
+   `:801` (`add_path_mapping`, target→link), `:750-775` (first-level-only symlink scan).
+   Done when: with a root removed from disk (or a directory replaced by an unreadable junction),
+   `raw_data` keeps those entries, `removed` is 0, and the counts land in the result payload.
+
+3. **Folder-tree merge under scope.**
+   What to do: replace the unconditional `sorted_discovered` assignment with the union rule from
+   "Must have"; keep the `folders_changed` comparison and the persist path unchanged. Unscoped
+   scans with nothing unreachable must produce exactly today's list.
+   References: `py/services/model_scanner.py` (walk loop records `discovered_folders`; `model_scanner.py:1738`
+   (`sorted_discovered`) and `:1739` (`folders_changed`) after the dedup pass).
+   Done when: a scoped scan keeps folders outside the scope, an offline root keeps its subtree, and
+   a full scan still drops folders deleted on disk.
+
+4. **Result payload + progress/cancel/complete messages.**
+   What to do: extend the `completed` broadcast with `scanned_roots`, `skipped_roots`,
+   `unavailable_paths`, `kept_unreachable`, `repaired`; the walk tracker already receives only the
+   scoped roots, so the progress line shows that root's label with `roots_total=1`.
+   References: `py/services/model_scanner.py` `_broadcast_scan_progress` (`:576`),
+   `_ReconcileWalkTracker` (`:266`), the completed broadcast at the end of `_reconcile_cache`.
+   Done when: a scoped scan emits `stage=reconcile_scan` with the single scoped label and a
+   `completed` payload carrying the new fields.
+
+5. **API surface.**
+   What to do: `scan_models` accepts repeated `roots` query params (400 on unknown root, 400 when
+   combined with `full_rebuild=true`); `get_model_roots` adds `root_details` (label, reachable,
+   model count via the shared prefix attribution) without touching `roots`.
+   References: `py/routes/handlers/model_handlers.py:1139` (`scan_models`), `:1165`
+   (`get_model_roots`), `py/routes/model_route_registrar.py:61-62`, `static/js/api/apiConfig.js:114`.
+   Done when: `tests/routes/test_lora_routes.py`-style coverage passes for the new params and the
+   backward-compatible `/roots` payload.
+
+6. **Preview 404 must not prune when the parent is unreachable.**
+   What to do: in `serve_preview`, before `_cleanup_stale_preview_url`, check
+   `os.path.isdir(os.path.dirname(resolved))`; if the directory itself is missing/unreachable,
+   return 404 **without** clearing caches. (Centralized sidecar mode puts the preview in the mirror
+   tree, so the check must use the preview file's own parent.)
+   References: `py/routes/handlers/preview_handlers.py:57` (404 branch), `:74-110`
+   (`_cleanup_stale_preview_url` → `clear_preview_by_path` + `_persist_current_cache`),
+   `tests/routes/test_preview_routes.py`.
+   Done when: a test asserts the cache keeps `preview_url` when the parent dir is absent and still
+   clears it when the file was really deleted from a reachable directory.
+
+### Wave 2 — labels
+
+7. **`_root_display_labels(roots)` (set-aware, order-independent).**
+   What to do: replace the single-root `_root_display_label`; compute over the sorted root list;
+   prepend real parent segments until unique; `(2)`/`(3)` fallback; 40-char middle-ellipsis; return
+   `{path: label}`. Use it in `_ReconcileWalkTracker.__init__` (progress) and in the `/roots`
+   handler so both always agree.
+   References: `py/services/model_scanner.py:117` (`_root_display_label`, current single-root
+   version), `:266` (`_ReconcileWalkTracker`).
+   Done when: unit tests cover `usb/loras` + `ssd/loras`, `a/models/loras` + `b/models/loras`,
+   Windows `G:\x\loras` + `H:\y\loras` → `G: loras` / `H: loras`, and the identical-path fallback.
+
+### Wave 3 — frontend
+
+8. **Refresh ▾ scope section.**
+   What to do: add an empty container to `templates/components/controls.html` inside
+   `.dropdown-menu` (`#refreshScopeMenu`) + a section title; on dropdown open, fetch
+   `endpoints.roots`, render one row per root (`data-action="scan-root"`, `data-root="<path>"`,
+   label + model count, `disabled` + "Offline" for unreachable), hide the section on the recipes
+   page (recipes have no roots); wire clicks by **event delegation** on the menu (the existing
+   `full-rebuild` item is bound with a direct `querySelector`, dynamic rows cannot be);
+   invalidate the cached list after a scan finishes; add CSS for the section + `max-height`/
+   `overflow-y` so 4+ roots stay usable.
+   References: `templates/components/controls.html:67-76`, `static/js/components/controls/PageControls.js:131`
+   (`data-action="refresh"`), `:220-260` (`initDropdowns` + `full-rebuild` wiring),
+   `static/js/api/apiConfig.js:118` (`roots` endpoint), `static/js/api/baseModelApi.js:1318`
+   (`fetchModelRoots`).
+   Done when: the menu lists roots with counts, an offline root is visibly disabled, and clicking a
+   row starts a scoped refresh.
+
+9. **Scoped request + toast.**
+   What to do: `refreshModels(fullRebuild, {roots})` appends repeated `roots` params; the
+   `completed` payload drives the toast (`added`/`removed`/`kept_unreachable`/`skipped_roots`);
+   offline rows toast `… is not reachable right now. Nothing was changed.` without a request.
+   References: `static/js/api/baseModelApi.js:514-602` (refreshModels, URL build at `:601`, toast
+   at `:618`), `static/js/components/controls/PageControls.js:485`.
+   Done when: the frontend test asserts the scoped URL and both toast variants.
+
+10. **i18n.**
+    What to do: add `loras.controls.refresh.scopeSection`, `.rootOffline`, `.rootModels`,
+    `toast.api.refreshCompleteScoped`, `toast.api.refreshKeptUnreachable`,
+    `toast.api.scanRootUnreachable` to `locales/en.json`, run
+    `python scripts/sync_translation_keys.py`, then stop (placeholders are the expected state until
+    translations are requested).
+    Done when: `pytest tests/i18n` passes and every locale has the keys.
+
+### Wave 4 — tests and verification
+
+11. **Backend tests** (`tests/services/test_model_scanner.py`, `tests/routes/test_lora_routes.py`,
+    `tests/routes/test_preview_routes.py`):
+    `test_reconcile_scoped_scan_leaves_other_roots_untouched`,
+    `test_reconcile_scoped_scan_removes_deleted_files_in_scope`,
+    `test_reconcile_scoped_scan_preserves_folder_tree_outside_scope`,
+    `test_reconcile_keeps_entries_of_unreachable_root`,
+    `test_reconcile_keeps_entries_under_unreadable_dir`,
+    `test_reconcile_keeps_entries_under_offline_first_level_symlink`,
+    `test_root_display_labels_dedupe_by_parent_segments`,
+    `test_scan_models_accepts_roots_param`, `test_scan_rejects_unknown_root`,
+    `test_scan_rejects_roots_with_full_rebuild`, `test_roots_endpoint_reports_details`,
+    `test_preview_404_keeps_cache_when_parent_dir_missing`.
+
+12. **Frontend tests**: extend `tests/frontend/api/baseModelApi.refresh.test.js` (scoped URL, both
+    toasts) and add `tests/frontend/components/controls/pageControls.scanRoots.test.js`
+    (rows rendered from `/roots`, offline row disabled, delegation wiring).
+
+13. **Full suites + sandbox eyeball**: `pytest -q`, `npx vitest run`, `npm run test:vue`; then a
+    sandboxed standalone instance with two roots and a slowed walk
+    (`LM_WALK_DELAY_S`-style `sitecustomize` hook) to eyeball the scoped progress line, the offline
+    row and the toast — the user verifies by eye.
+
+### Wave 5 — P2 (folder scope), only if approved
+
+14. `folder=<rel>` in the scan endpoint + `_ReconcileScope.folder`, the sidebar menu entry, the
+    context-menu regression test update, and the "folder in several roots" semantics (scan every
+    reachable root that has the relative path; report per root).
+
+## Known limitations (accepted)
+
+- **Nested symlinks** (a symlink *below* a root pointing at another drive) are only covered when
+  `os.walk` fails to enter the target (Windows junctions, permission errors). A broken symlink that
+  `os.walk` classifies as a non-directory (typical on POSIX) is not detected: its entries are pruned
+  as today and come back on the next scan once the target is reachable (sidecars carry the sha256,
+  so no re-hash). Verify the Windows junction behaviour before writing release notes.
+- Only **first-level** symlinks are known to `config` (by design, `config.py:750-775`), so the
+  symlink reachability check inherits that limit.
+- A scoped scan of a folder does not re-read metadata for unchanged files (unchanged behaviour).
+- Empty folders removed on disk can linger in the sidebar after a scoped scan (the folder list is
+  unioned rather than replaced whenever the scan did not verify every root); the next full refresh
+  drops them.
+- `root_details[].reachable` is a live `os.path.exists()` per root, so a root that disappears
+  mid-session shows as offline; a root that was already gone at startup is filtered out by
+  `Config` and therefore absent from the list.
+
+## Verification checklist
+
+- [ ] `pytest -q` green, `npx vitest run` green, `npm run test:vue` green.
+- [ ] `python scripts/sync_translation_keys.py --dry-run` reports no pending changes.
+- [ ] Sandbox: 2 roots, one offline → scoped scan of the online root reports `added`, keeps the
+      offline root's models, and the grid/sidebar still show them.
+- [ ] Sandbox: preview of an offline root's model returns 404 and the DB keeps `preview_url`.
+- [ ] Release note wording agreed for the behaviour change (decision 1).
diff --git a/locales/de.json b/locales/de.json
index 9912af2e..ae043631 100644
--- a/locales/de.json
+++ b/locales/de.json
@@ -918,7 +918,10 @@
             "refresh": {
                 "title": "Modelliste aktualisieren",
                 "full": "Cache neu aufbauen",
-                "fullTooltip": "Alle Modelldetails aus Metadatendateien neu laden – nutzen, wenn die Bibliothek veraltet wirkt oder nach manuellen Änderungen."
+                "fullTooltip": "Alle Modelldetails aus Metadatendateien neu laden – nutzen, wenn die Bibliothek veraltet wirkt oder nach manuellen Änderungen.",
+                "scopeSection": "[TODO: Translate] Scan one folder",
+                "rootOffline": "[TODO: Translate] Offline",
+                "rootModels": "[TODO: Translate] {count} models"
             },
             "fetch": {
                 "title": "Metadaten von CivitAI abrufen",
@@ -2804,7 +2807,10 @@
             "exampleImagesDownloadFailed": "Fehler beim Herunterladen der Beispielbilder: {message}",
             "moveFailed": "Element konnte nicht verschoben werden: {message}",
             "copiedToClipboard": "In die Zwischenablage kopiert",
-            "downloadStarted": "Download gestartet"
+            "downloadStarted": "Download gestartet",
+            "refreshCompleteScoped": "[TODO: Translate] Scanned {scope}: {added} new, {removed} removed",
+            "refreshKeptUnreachable": "[TODO: Translate] {count} models kept: {paths} not reachable",
+            "scanRootUnreachable": "[TODO: Translate] {scope} is not reachable right now. Nothing was changed."
         },
         "agent": {
             "llmNotConfigured": "KI-Anbieter nicht konfiguriert. Aktivieren Sie ihn unter Einstellungen → KI-Anbieter.",
diff --git a/locales/en.json b/locales/en.json
index 14caaeda..ff08bf1e 100644
--- a/locales/en.json
+++ b/locales/en.json
@@ -918,7 +918,10 @@
       "refresh": {
         "title": "Refresh model list",
         "full": "Rebuild Cache",
-        "fullTooltip": "Reload all model details from metadata files—use if the library looks out of date or after manual edits."
+        "fullTooltip": "Reload all model details from metadata files—use if the library looks out of date or after manual edits.",
+        "scopeSection": "Scan one folder",
+        "rootOffline": "Offline",
+        "rootModels": "{count} models"
       },
       "fetch": {
         "title": "Fetch metadata from CivitAI",
@@ -2804,7 +2807,10 @@
       "exampleImagesDownloadFailed": "Failed to download example images: {message}",
       "moveFailed": "Failed to move item: {message}",
       "copiedToClipboard": "Copied to clipboard",
-      "downloadStarted": "Download started"
+      "downloadStarted": "Download started",
+      "refreshCompleteScoped": "Scanned {scope}: {added} new, {removed} removed",
+      "refreshKeptUnreachable": "{count} models kept: {paths} not reachable",
+      "scanRootUnreachable": "{scope} is not reachable right now. Nothing was changed."
     },
     "agent": {
       "llmNotConfigured": "AI provider not configured. Enable it in Settings → AI Provider.",
diff --git a/locales/es.json b/locales/es.json
index 1248cadb..42229a4b 100644
--- a/locales/es.json
+++ b/locales/es.json
@@ -918,7 +918,10 @@
             "refresh": {
                 "title": "Actualizar lista de modelos",
                 "full": "Reconstruir caché",
-                "fullTooltip": "Vuelve a cargar todos los detalles desde los archivos de metadatos; úsalo si la biblioteca parece desactualizada o tras ediciones manuales."
+                "fullTooltip": "Vuelve a cargar todos los detalles desde los archivos de metadatos; úsalo si la biblioteca parece desactualizada o tras ediciones manuales.",
+                "scopeSection": "[TODO: Translate] Scan one folder",
+                "rootOffline": "[TODO: Translate] Offline",
+                "rootModels": "[TODO: Translate] {count} models"
             },
             "fetch": {
                 "title": "Obtener metadatos de CivitAI",
@@ -2804,7 +2807,10 @@
             "exampleImagesDownloadFailed": "Error al descargar imágenes de ejemplo: {message}",
             "moveFailed": "No se pudo mover el elemento: {message}",
             "copiedToClipboard": "Copiado al portapapeles",
-            "downloadStarted": "Descarga iniciada"
+            "downloadStarted": "Descarga iniciada",
+            "refreshCompleteScoped": "[TODO: Translate] Scanned {scope}: {added} new, {removed} removed",
+            "refreshKeptUnreachable": "[TODO: Translate] {count} models kept: {paths} not reachable",
+            "scanRootUnreachable": "[TODO: Translate] {scope} is not reachable right now. Nothing was changed."
         },
         "agent": {
             "llmNotConfigured": "Proveedor de IA no configurado. Actívelo en Configuración → Proveedor de IA.",
diff --git a/locales/fr.json b/locales/fr.json
index 4ff0e3fa..5aff7118 100644
--- a/locales/fr.json
+++ b/locales/fr.json
@@ -918,7 +918,10 @@
             "refresh": {
                 "title": "Actualiser la liste des modèles",
                 "full": "Reconstruire le cache",
-                "fullTooltip": "Recharge tous les détails des modèles depuis les fichiers de métadonnées — à utiliser si la bibliothèque paraît obsolète ou après des modifications manuelles."
+                "fullTooltip": "Recharge tous les détails des modèles depuis les fichiers de métadonnées — à utiliser si la bibliothèque paraît obsolète ou après des modifications manuelles.",
+                "scopeSection": "[TODO: Translate] Scan one folder",
+                "rootOffline": "[TODO: Translate] Offline",
+                "rootModels": "[TODO: Translate] {count} models"
             },
             "fetch": {
                 "title": "Récupérer les métadonnées depuis CivitAI",
@@ -2804,7 +2807,10 @@
             "exampleImagesDownloadFailed": "Échec du téléchargement des images d'exemple : {message}",
             "moveFailed": "Échec du déplacement de l'élément : {message}",
             "copiedToClipboard": "Copié dans le presse-papiers",
-            "downloadStarted": "Téléchargement démarré"
+            "downloadStarted": "Téléchargement démarré",
+            "refreshCompleteScoped": "[TODO: Translate] Scanned {scope}: {added} new, {removed} removed",
+            "refreshKeptUnreachable": "[TODO: Translate] {count} models kept: {paths} not reachable",
+            "scanRootUnreachable": "[TODO: Translate] {scope} is not reachable right now. Nothing was changed."
         },
         "agent": {
             "llmNotConfigured": "Fournisseur d'IA non configuré. Activez-le dans Paramètres → Fournisseur d'IA.",
diff --git a/locales/he.json b/locales/he.json
index ed15bde8..acd6452d 100644
--- a/locales/he.json
+++ b/locales/he.json
@@ -918,7 +918,10 @@
             "refresh": {
                 "title": "רענן רשימת מודלים",
                 "full": "בניית מטמון מחדש",
-                "fullTooltip": "טוען מחדש את כל פרטי המודלים מקבצי המטא-נתונים – לשימוש אם הספרייה נראית לא מעודכנת או לאחר עריכות ידניות."
+                "fullTooltip": "טוען מחדש את כל פרטי המודלים מקבצי המטא-נתונים – לשימוש אם הספרייה נראית לא מעודכנת או לאחר עריכות ידניות.",
+                "scopeSection": "[TODO: Translate] Scan one folder",
+                "rootOffline": "[TODO: Translate] Offline",
+                "rootModels": "[TODO: Translate] {count} models"
             },
             "fetch": {
                 "title": "אחזר מטא-נתונים מ-CivitAI",
@@ -2804,7 +2807,10 @@
             "exampleImagesDownloadFailed": "הורדת תמונות הדוגמה נכשלה: {message}",
             "moveFailed": "לא ניתן היה להעביר את הפריט: {message}",
             "copiedToClipboard": "הועתק ללוח",
-            "downloadStarted": "ההורדה החלה"
+            "downloadStarted": "ההורדה החלה",
+            "refreshCompleteScoped": "[TODO: Translate] Scanned {scope}: {added} new, {removed} removed",
+            "refreshKeptUnreachable": "[TODO: Translate] {count} models kept: {paths} not reachable",
+            "scanRootUnreachable": "[TODO: Translate] {scope} is not reachable right now. Nothing was changed."
         },
         "agent": {
             "llmNotConfigured": "ספק AI לא הוגדר. הפעל אותו בהגדרות → ספק AI.",
diff --git a/locales/ja.json b/locales/ja.json
index d0553547..f26122d0 100644
--- a/locales/ja.json
+++ b/locales/ja.json
@@ -918,7 +918,10 @@
             "refresh": {
                 "title": "モデルリストを更新",
                 "full": "キャッシュを再構築",
-                "fullTooltip": "メタデータファイルから全モデル情報を再読み込みします。リストが古いと感じるときや手動編集後に使用してください。"
+                "fullTooltip": "メタデータファイルから全モデル情報を再読み込みします。リストが古いと感じるときや手動編集後に使用してください。",
+                "scopeSection": "[TODO: Translate] Scan one folder",
+                "rootOffline": "[TODO: Translate] Offline",
+                "rootModels": "[TODO: Translate] {count} models"
             },
             "fetch": {
                 "title": "CivitAIからメタデータを取得",
@@ -2804,7 +2807,10 @@
             "exampleImagesDownloadFailed": "例画像のダウンロードに失敗しました：{message}",
             "moveFailed": "アイテムを移動できませんでした: {message}",
             "copiedToClipboard": "クリップボードにコピーしました",
-            "downloadStarted": "ダウンロードを開始しました"
+            "downloadStarted": "ダウンロードを開始しました",
+            "refreshCompleteScoped": "[TODO: Translate] Scanned {scope}: {added} new, {removed} removed",
+            "refreshKeptUnreachable": "[TODO: Translate] {count} models kept: {paths} not reachable",
+            "scanRootUnreachable": "[TODO: Translate] {scope} is not reachable right now. Nothing was changed."
         },
         "agent": {
             "llmNotConfigured": "AIプロバイダーが設定されていません。設定 → AIプロバイダーで有効にしてください。",
diff --git a/locales/ko.json b/locales/ko.json
index 89c30126..5d325b20 100644
--- a/locales/ko.json
+++ b/locales/ko.json
@@ -918,7 +918,10 @@
             "refresh": {
                 "title": "모델 목록 새로고침",
                 "full": "캐시 재구성",
-                "fullTooltip": "메타데이터 파일에서 모든 모델 정보를 다시 불러옵니다. 라이브러리가 오래되어 보이거나 수동 수정 후에 사용하세요."
+                "fullTooltip": "메타데이터 파일에서 모든 모델 정보를 다시 불러옵니다. 라이브러리가 오래되어 보이거나 수동 수정 후에 사용하세요.",
+                "scopeSection": "[TODO: Translate] Scan one folder",
+                "rootOffline": "[TODO: Translate] Offline",
+                "rootModels": "[TODO: Translate] {count} models"
             },
             "fetch": {
                 "title": "CivitAI에서 메타데이터 가져오기",
@@ -2804,7 +2807,10 @@
             "exampleImagesDownloadFailed": "예시 이미지 다운로드 실패: {message}",
             "moveFailed": "항목을 이동하지 못했습니다: {message}",
             "copiedToClipboard": "클립보드에 복사됨",
-            "downloadStarted": "다운로드 시작됨"
+            "downloadStarted": "다운로드 시작됨",
+            "refreshCompleteScoped": "[TODO: Translate] Scanned {scope}: {added} new, {removed} removed",
+            "refreshKeptUnreachable": "[TODO: Translate] {count} models kept: {paths} not reachable",
+            "scanRootUnreachable": "[TODO: Translate] {scope} is not reachable right now. Nothing was changed."
         },
         "agent": {
             "llmNotConfigured": "AI 제공자가 설정되지 않았습니다. 설정 → AI 제공자에서 활성화하세요.",
diff --git a/locales/ru.json b/locales/ru.json
index 2c86f25e..eb14ce66 100644
--- a/locales/ru.json
+++ b/locales/ru.json
@@ -918,7 +918,10 @@
             "refresh": {
                 "title": "Обновить список моделей",
                 "full": "Перестроить кэш",
-                "fullTooltip": "Перечитывает все данные моделей из файлов метаданных — используйте, если библиотека выглядит устаревшей или после ручных правок."
+                "fullTooltip": "Перечитывает все данные моделей из файлов метаданных — используйте, если библиотека выглядит устаревшей или после ручных правок.",
+                "scopeSection": "[TODO: Translate] Scan one folder",
+                "rootOffline": "[TODO: Translate] Offline",
+                "rootModels": "[TODO: Translate] {count} models"
             },
             "fetch": {
                 "title": "Получить метаданные с CivitAI",
@@ -2804,7 +2807,10 @@
             "exampleImagesDownloadFailed": "Не удалось загрузить примеры изображений: {message}",
             "moveFailed": "Не удалось переместить элемент: {message}",
             "copiedToClipboard": "Скопировано в буфер обмена",
-            "downloadStarted": "Загрузка начата"
+            "downloadStarted": "Загрузка начата",
+            "refreshCompleteScoped": "[TODO: Translate] Scanned {scope}: {added} new, {removed} removed",
+            "refreshKeptUnreachable": "[TODO: Translate] {count} models kept: {paths} not reachable",
+            "scanRootUnreachable": "[TODO: Translate] {scope} is not reachable right now. Nothing was changed."
         },
         "agent": {
             "llmNotConfigured": "Поставщик ИИ не настроен. Включите его в Настройки → Поставщик ИИ.",
diff --git a/locales/zh-CN.json b/locales/zh-CN.json
index 8018e0dc..7fedcd22 100644
--- a/locales/zh-CN.json
+++ b/locales/zh-CN.json
@@ -918,7 +918,10 @@
             "refresh": {
                 "title": "刷新模型列表",
                 "full": "重建缓存",
-                "fullTooltip": "从元数据文件重新加载所有模型信息；用于列表过时或手动编辑后。"
+                "fullTooltip": "从元数据文件重新加载所有模型信息；用于列表过时或手动编辑后。",
+                "scopeSection": "[TODO: Translate] Scan one folder",
+                "rootOffline": "[TODO: Translate] Offline",
+                "rootModels": "[TODO: Translate] {count} models"
             },
             "fetch": {
                 "title": "从 CivitAI 获取元数据",
@@ -2804,7 +2807,10 @@
             "exampleImagesDownloadFailed": "示例图片下载失败：{message}",
             "moveFailed": "移动条目失败：{message}",
             "copiedToClipboard": "已复制到剪贴板",
-            "downloadStarted": "下载已开始"
+            "downloadStarted": "下载已开始",
+            "refreshCompleteScoped": "[TODO: Translate] Scanned {scope}: {added} new, {removed} removed",
+            "refreshKeptUnreachable": "[TODO: Translate] {count} models kept: {paths} not reachable",
+            "scanRootUnreachable": "[TODO: Translate] {scope} is not reachable right now. Nothing was changed."
         },
         "agent": {
             "llmNotConfigured": "AI 提供商未配置。请在 设置 → AI 提供商 中进行配置。",
diff --git a/locales/zh-TW.json b/locales/zh-TW.json
index 0ca955b0..1f92cd9e 100644
--- a/locales/zh-TW.json
+++ b/locales/zh-TW.json
@@ -918,7 +918,10 @@
             "refresh": {
                 "title": "重新整理模型列表",
                 "full": "重建快取",
-                "fullTooltip": "從中繼資料檔重新載入所有模型資訊；適用於清單過時或手動編輯後。"
+                "fullTooltip": "從中繼資料檔重新載入所有模型資訊；適用於清單過時或手動編輯後。",
+                "scopeSection": "[TODO: Translate] Scan one folder",
+                "rootOffline": "[TODO: Translate] Offline",
+                "rootModels": "[TODO: Translate] {count} models"
             },
             "fetch": {
                 "title": "從 CivitAI 取得 metadata",
@@ -2804,7 +2807,10 @@
             "exampleImagesDownloadFailed": "下載範例圖片失敗：{message}",
             "moveFailed": "移動項目失敗：{message}",
             "copiedToClipboard": "已複製到剪貼簿",
-            "downloadStarted": "下載已開始"
+            "downloadStarted": "下載已開始",
+            "refreshCompleteScoped": "[TODO: Translate] Scanned {scope}: {added} new, {removed} removed",
+            "refreshKeptUnreachable": "[TODO: Translate] {count} models kept: {paths} not reachable",
+            "scanRootUnreachable": "[TODO: Translate] {scope} is not reachable right now. Nothing was changed."
         },
         "agent": {
             "llmNotConfigured": "AI 提供者尚未設定。請在 設定 → AI 提供者 中進行設定。",
diff --git a/py/config.py b/py/config.py
index 8ec4b9af..20f9e1a2 100644
--- a/py/config.py
+++ b/py/config.py
@@ -798,6 +798,16 @@ class Config:
         except Exception as e:
             logger.error(f"Error scanning links in {root}: {e}")
 
+    def iter_path_mappings(self) -> List[Tuple[str, str]]:
+        """Return the known ``(physical target, virtual link)`` symlink pairs.
+
+        Only symlinks directly under a model root are tracked (see
+        :meth:`_scan_symbolic_links`), so callers must treat this as a partial
+        view of the on-disk link layout — enough to notice that a linked drive
+        went away, not enough to resolve nested links.
+        """
+        return list(self._path_mappings.items())
+
     def add_path_mapping(self, link_path: str, target_path: str):
         """Add a symbolic link path mapping
         target_path: actual target path
diff --git a/py/routes/handlers/model_handlers.py b/py/routes/handlers/model_handlers.py
index 2072fb2c..1adc9d39 100644
--- a/py/routes/handlers/model_handlers.py
+++ b/py/routes/handlers/model_handlers.py
@@ -26,6 +26,7 @@ from ...services.connectivity_guard import (
 )
 from ...services.metadata_sync_service import MetadataSyncService
 from ...services.model_file_service import ModelMoveService
+from ...services.model_scanner import ReconcileScope
 from ...services.preview_asset_service import PreviewAssetService
 from ...services.service_registry import ServiceRegistry
 from ...services.settings_manager import SettingsManager, get_settings_manager
@@ -1139,8 +1140,30 @@ class ModelQueryHandler:
     async def scan_models(self, request: web.Request) -> web.Response:
         try:
             full_rebuild = request.query.get("full_rebuild", "false").lower() == "true"
-            await self._service.scan_models(
-                force_refresh=True, rebuild_cache=full_rebuild
+            requested_roots = [
+                value for value in request.query.getall("roots", []) if value
+            ]
+            if requested_roots and full_rebuild:
+                return web.json_response(
+                    {
+                        "error": "Scoped scans are not supported with "
+                        "full_rebuild=true; a full rebuild always walks every root"
+                    },
+                    status=400,
+                )
+
+            scope = None
+            if requested_roots:
+                configured = self._service.get_model_roots()
+                unknown = [root for root in requested_roots if root not in configured]
+                if unknown:
+                    return web.json_response(
+                        {"error": "Unknown model root(s)", "roots": unknown}, status=400
+                    )
+                scope = ReconcileScope(roots=tuple(requested_roots))
+
+            summary = await self._service.scan_models(
+                force_refresh=True, rebuild_cache=full_rebuild, scope=scope
             )
             _broadcast_models_changed()
             if self._service.scanner.is_cancelled():
@@ -1150,12 +1173,13 @@ class ModelQueryHandler:
                         "message": f"{self._service.model_type.capitalize()} scan cancelled",
                     }
                 )
-            return web.json_response(
-                {
-                    "status": "success",
-                    "message": f"{self._service.model_type.capitalize()} scan completed",
-                }
-            )
+            payload: Dict[str, Any] = {
+                "status": "success",
+                "message": f"{self._service.model_type.capitalize()} scan completed",
+            }
+            if summary:
+                payload.update(summary)
+            return web.json_response(payload)
         except Exception as exc:
             self._logger.error(
                 "Error scanning %ss: %s", self._service.model_type, exc, exc_info=True
@@ -1165,7 +1189,14 @@ class ModelQueryHandler:
     async def get_model_roots(self, request: web.Request) -> web.Response:
         try:
             roots = self._service.get_model_roots()
-            return web.json_response({"success": True, "roots": roots})
+            try:
+                root_details = self._service.describe_model_roots()
+            except Exception as exc:  # pragma: no cover - defensive
+                self._logger.debug("Root details unavailable: %s", exc)
+                root_details = []
+            return web.json_response(
+                {"success": True, "roots": roots, "root_details": root_details}
+            )
         except Exception as exc:
             self._logger.error(
                 "Error getting %s roots: %s",
diff --git a/py/routes/handlers/preview_handlers.py b/py/routes/handlers/preview_handlers.py
index c4a9edf4..be28c4f8 100644
--- a/py/routes/handlers/preview_handlers.py
+++ b/py/routes/handlers/preview_handlers.py
@@ -54,7 +54,18 @@ class PreviewHandler:
 
         if not resolved.is_file():
             logger.debug("Preview file not found at %s", str(resolved))
-            asyncio.create_task(self._cleanup_stale_preview_url(normalized))
+            if resolved.parent.is_dir():
+                # The file is really gone from a reachable directory, so the
+                # cached preview_url is stale and can be cleared.
+                asyncio.create_task(self._cleanup_stale_preview_url(normalized))
+            else:
+                # The directory itself is unreachable (drive switched off,
+                # unmounted share). Nothing was deleted: keep the cached
+                # preview_url so the card recovers when the drive is back.
+                logger.debug(
+                    "Preview directory unreachable, keeping cached preview_url: %s",
+                    str(resolved.parent),
+                )
             raise web.HTTPNotFound(text="Preview file not found")
 
         # aiohttp's FileResponse handles range requests, content headers, and
diff --git a/py/services/base_model_service.py b/py/services/base_model_service.py
index 228192aa..b91645d5 100644
--- a/py/services/base_model_service.py
+++ b/py/services/base_model_service.py
@@ -27,6 +27,7 @@ from ..utils.civitai_utils import build_civitai_model_page_url
 logger = logging.getLogger(__name__)
 
 if TYPE_CHECKING:
+    from .model_scanner import ReconcileScope
     from .model_update_service import ModelUpdateService
 
 
@@ -936,12 +937,25 @@ class BaseModelService(ABC):
         return self.scanner.get_hash_by_path(file_path)
 
     async def scan_models(
-        self, force_refresh: bool = False, rebuild_cache: bool = False
-    ):
-        """Trigger model scanning"""
-        return await self.scanner.get_cached_data(
-            force_refresh=force_refresh, rebuild_cache=rebuild_cache
+        self,
+        force_refresh: bool = False,
+        rebuild_cache: bool = False,
+        scope: Optional["ReconcileScope"] = None,
+    ) -> Optional[Dict[str, Any]]:
+        """Trigger model scanning, optionally restricted to a scope.
+
+        Returns the reconcile summary (added / removed / repaired / skipped
+        roots / kept entries) for incremental scans, ``None`` for a full
+        rebuild.
+        """
+        await self.scanner.get_cached_data(
+            force_refresh=force_refresh, rebuild_cache=rebuild_cache, scope=scope
         )
+        return self.scanner.last_reconcile_summary
+
+    def describe_model_roots(self) -> List[Dict[str, Any]]:
+        """Describe configured roots (label / reachability / cached count)."""
+        return self.scanner.describe_model_roots()
 
     async def get_model_info_by_name(self, name: str):
         """Get model information by name"""
diff --git a/py/services/model_scanner.py b/py/services/model_scanner.py
index 477873b6..b982e015 100644
--- a/py/services/model_scanner.py
+++ b/py/services/model_scanner.py
@@ -114,13 +114,84 @@ def _new_file_pass_progress(processed: int, total: int) -> int:
     return _WALK_PROGRESS_SHARE + min(49, int(ratio * 49))
 
 
-def _root_display_label(root: str) -> str:
-    """Short label identifying a model root in progress messages."""
-    drive, _tail = os.path.splitdrive(root)
-    if drive:
-        return drive
-    normalized = root.rstrip("/\\")
-    return os.path.basename(normalized) or root
+# Maximum length of a root label in progress messages and menus; the full path
+# always stays available in the tooltip.
+_ROOT_LABEL_MAX_LENGTH = 40
+
+
+def _truncate_label(label: str, limit: int = _ROOT_LABEL_MAX_LENGTH) -> str:
+    """Middle-truncate an over-long label."""
+    if len(label) <= limit:
+        return label
+    keep = max(limit - 3, 1)
+    head = (keep + 1) // 2
+    tail = keep - head
+    if not tail:
+        return f"{label[:head]}..."
+    return f"{label[:head]}...{label[-tail:]}"
+
+
+def _root_path_parts(root: str) -> Tuple[str, List[str]]:
+    """Split a root into its drive prefix (Windows) and its path segments."""
+    drive, tail = os.path.splitdrive(root)
+    normalized = tail.replace("\\", "/").strip("/")
+    return drive, [part for part in normalized.split("/") if part]
+
+
+def _root_display_labels(roots: Sequence[str]) -> Dict[str, str]:
+    """Return a unique, human-friendly label for every root in the set.
+
+    The label starts as the last path segment (prefixed with the drive letter on
+    Windows, e.g. ``G: loras``) and grows leftwards with **real parent path
+    segments** until it is unique inside the set (``usb/loras`` vs
+    ``ssd/loras``). Roots that still render identically (Windows case variants,
+    a duplicated config entry) get a deterministic numeric suffix.
+
+    Labels are a property of the whole set, so they are computed from the sorted
+    root list: the same configuration always yields the same labels, whatever
+    order the roots are walked in.
+    """
+    if not roots:
+        return {}
+
+    parts_by_root = {root: _root_path_parts(root) for root in roots}
+    depth = {root: (1 if parts_by_root[root][1] else 0) for root in roots}
+
+    def _render(root: str) -> str:
+        drive, parts = parts_by_root[root]
+        if not parts:
+            return drive or root
+        take = max(min(depth[root], len(parts)), 1)
+        tail = "/".join(parts[len(parts) - take:])
+        return f"{drive} {tail}" if drive else tail
+
+    # Grow the depth of colliding labels until they can be told apart.
+    while True:
+        groups: Dict[str, List[str]] = {}
+        for root in roots:
+            groups.setdefault(_render(root), []).append(root)
+        colliding = [group for group in groups.values() if len(group) > 1]
+        if not colliding:
+            break
+        grew = False
+        for group in colliding:
+            for root in group:
+                if depth[root] < len(parts_by_root[root][1]):
+                    depth[root] += 1
+                    grew = True
+        if not grew:
+            break
+
+    labels = {root: _render(root) for root in roots}
+    fallback: Dict[str, List[str]] = {}
+    for root in sorted(roots):
+        fallback.setdefault(labels[root], []).append(root)
+    for label, group in fallback.items():
+        if len(group) > 1:
+            for index, root in enumerate(group, start=1):
+                labels[root] = f"{label} ({index})"
+
+    return {root: _truncate_label(label) for root, label in labels.items()}
 
 
 def _normalized_root_prefix(root: str) -> str:
@@ -131,34 +202,136 @@ def _normalized_root_prefix(root: str) -> str:
     return prefix.lower() if _CASE_INSENSITIVE_PATHS else prefix
 
 
-def _count_cached_entries_per_root(
-    cached_paths: Set[str], roots: Sequence[str]
-) -> Dict[str, int]:
-    """Attribute cached entries to model roots (longest prefix wins).
+def _path_matches_prefix(path: str, prefix: str) -> bool:
+    """Match a cached business path against a normalized scope prefix."""
+    candidate = path.lower() if _CASE_INSENSITIVE_PATHS else path
+    return candidate.startswith(prefix)
 
+
+def _scope_prefix(root: str, folder: Optional[str] = None) -> str:
+    """Normalized prefix covering a root, or a folder inside that root."""
+    prefix = _normalized_root_prefix(root)
+    if folder:
+        relative = folder.replace("\\", "/").strip("/")
+        if relative:
+            if _CASE_INSENSITIVE_PATHS:
+                relative = relative.lower()
+            prefix = f"{prefix}{relative}/"
+    return prefix
+
+
+def _scope_walk_path(root: str, folder: Optional[str] = None) -> str:
+    """Filesystem path a scoped walk starts at (the root itself when unscoped)."""
+    if not folder:
+        return root
+    relative = folder.replace("\\", "/").strip("/")
+    if not relative:
+        return root
+    return os.path.join(root, *relative.split("/"))
+
+
+@dataclass(frozen=True)
+class ReconcileScope:
+    """Restrict a reconcile to some of the configured roots and/or a folder.
+
+    ``roots=None`` means "every configured root". ``folder`` is a root-relative
+    folder in forward-slash form and applies to each root in the scope.
+    """
+
+    roots: Optional[Tuple[str, ...]] = None
+    folder: Optional[str] = None
+
+
+class _UnreachablePaths:
+    """Prefixes this reconcile could not read; their entries are never pruned.
+
+    Populated from three sources: a configured root that is not reachable, a
+    directory ``os.walk`` failed to enter (permissions, I/O error, a Windows
+    junction to an offline drive), and a known first-level symlink whose target
+    is not a directory. Cached entries under these prefixes are reported instead
+    of removed, so switching a drive off can no longer wipe its models.
+    """
+
+    def __init__(self) -> None:
+        self._lock = threading.Lock()
+        self._prefixes: List[str] = []
+        self._details: Dict[str, Dict[str, Any]] = {}
+
+    def add(self, path: str, reason: str) -> None:
+        prefix = _normalized_root_prefix(path)
+        with self._lock:
+            if prefix in self._details:
+                return
+            self._details[prefix] = {
+                'path': path.replace(os.sep, '/'),
+                'reason': reason,
+                'kept': 0,
+            }
+            self._prefixes.append(prefix)
+
+    def match(self, cached_path: str) -> Optional[str]:
+        """Return the prefix covering ``cached_path``, if any."""
+        for prefix in self._prefixes:
+            if _path_matches_prefix(cached_path, prefix):
+                return prefix
+        return None
+
+    def record_kept(self, prefix: str, amount: int = 1) -> None:
+        detail = self._details.get(prefix)
+        if detail is not None:
+            detail['kept'] += amount
+
+    def total_kept(self) -> int:
+        return sum(detail['kept'] for detail in self._details.values())
+
+    def count(self) -> int:
+        return len(self._details)
+
+    def has_entries(self) -> bool:
+        return bool(self._details)
+
+    def payload(self, limit: int = 5) -> List[Dict[str, Any]]:
+        """Most affected prefixes first, capped for the progress payload."""
+        entries = sorted(
+            self._details.values(), key=lambda detail: detail['kept'], reverse=True
+        )
+        return [dict(entry) for entry in entries[:limit]]
+
+
+def _count_cached_entries_for_prefixes(
+    cached_paths: Set[str], prefixes: Sequence[Tuple[str, str]]
+) -> Dict[str, int]:
+    """Count cached entries per ``(key, normalized prefix)`` pair.
+
+    Longest prefix wins, so a folder scope counts only the entries inside it.
     Used as the walk-workload weight for progress reporting: the walk itself is
     what discovers the real file count, so the cached entry count is the only
     estimate available up front.
     """
-    counts: Dict[str, int] = {root: 0 for root in roots}
-    if not roots:
+    counts: Dict[str, int] = {key: 0 for key, _prefix in prefixes}
+    if not prefixes:
         return counts
 
-    prefixes = sorted(
-        ((_normalized_root_prefix(root), root) for root in roots),
-        key=lambda item: len(item[0]),
-        reverse=True,
-    )
+    ordered = sorted(prefixes, key=lambda item: len(item[1]), reverse=True)
     case_insensitive = _CASE_INSENSITIVE_PATHS
     for path in cached_paths:
         candidate = path.lower() if case_insensitive else path
-        for prefix, root in prefixes:
+        for key, prefix in ordered:
             if candidate.startswith(prefix):
-                counts[root] += 1
+                counts[key] += 1
                 break
     return counts
 
 
+def _count_cached_entries_per_root(
+    cached_paths: Set[str], roots: Sequence[str]
+) -> Dict[str, int]:
+    """Attribute cached entries to model roots (longest prefix wins)."""
+    return _count_cached_entries_for_prefixes(
+        cached_paths, [(root, _normalized_root_prefix(root)) for root in roots]
+    )
+
+
 def _root_device_key(root: str) -> str:
     """Group key identifying the storage device that holds a root.
 
@@ -273,10 +446,19 @@ class _ReconcileWalkTracker:
     they finish.
     """
 
-    def __init__(self, roots: Sequence[str], expected: Mapping[str, int]) -> None:
+    def __init__(
+        self,
+        roots: Sequence[str],
+        expected: Mapping[str, int],
+        labels: Optional[Mapping[str, str]] = None,
+    ) -> None:
         self._lock = threading.Lock()
         self._roots: List[str] = list(roots)
-        self._labels = {root: _root_display_label(root) for root in self._roots}
+        # Callers that already labelled the full configured root set pass those
+        # labels in, so the progress line and the refresh menu never disagree on
+        # how a root is named.
+        resolved = dict(labels) if labels else _root_display_labels(self._roots)
+        self._labels = {root: resolved.get(root) or root for root in self._roots}
         self._expected = {
             root: max(int(expected.get(root, 0) or 0), 0) for root in self._roots
         }
@@ -373,15 +555,28 @@ def _walk_root_for_reconcile(
     excluded_models: Set[str],
     is_cancelled: Callable[[], bool],
     report_progress: Callable[[int], None],
+    walk_path: Optional[str] = None,
+    unreachable: Optional[_UnreachablePaths] = None,
 ) -> _RootWalkResult:
     """Walk one model root and classify every model file found.
 
+    ``walk_path`` defaults to the root itself; a folder scope starts the walk
+    deeper but still resolves ``folder``/``file_path`` against ``root_path`` so
+    cache entries keep their library-relative shape.
+
     Runs synchronously (worker thread) and never mutates scanner state: all
     cache updates happen on the event loop once every root has been walked.
     """
     result = _RootWalkResult(root_path=root_path)
     stale_seen: Set[str] = set()
     files_since_report = 0
+    walk_start = walk_path or root_path
+
+    def _on_walk_error(error: OSError) -> None:
+        """Record a directory the walk could not enter (offline/denied)."""
+        filename = getattr(error, 'filename', None)
+        if filename and unreachable is not None:
+            unreachable.add(str(filename), 'unreadable_dir')
 
     def mark_stale_if_needed(cached_path: str) -> None:
         """Queue a cached path for file_name repair when it drifted."""
@@ -395,7 +590,9 @@ def _walk_root_for_reconcile(
         stale_seen.add(cached_path)
         result.stale_paths.append(cached_path)
 
-    for root, dirnames, files in os.walk(root_path, followlinks=True):
+    for root, dirnames, files in os.walk(
+        walk_start, followlinks=True, onerror=_on_walk_error
+    ):
         dirnames[:] = [d for d in dirnames if not _is_excluded_dir(d)]
 
         real_root = os.path.realpath(root)
@@ -554,6 +751,8 @@ class ModelScanner:
         self._defer_persist_depth = 0
         self._deferred_persist_pending = False
         self._autov3_backfill_scheduled = False  # One-time AutoV3 backfill trigger per process
+        # Summary of the last incremental reconcile (see last_reconcile_summary)
+        self._last_reconcile_summary: Optional[Dict[str, Any]] = None
         # Guard against concurrent all-folders backfill walks (cold fallback
         # for persisted snapshots that predate folder recording).
         self._all_folders_backfill_running = False
@@ -1334,12 +1533,19 @@ class ModelScanner:
             asyncio.set_event_loop(None)
             loop.close()
 
-    async def get_cached_data(self, force_refresh: bool = False, rebuild_cache: bool = False) -> ModelCache:
+    async def get_cached_data(
+        self,
+        force_refresh: bool = False,
+        rebuild_cache: bool = False,
+        scope: Optional[ReconcileScope] = None,
+    ) -> ModelCache:
         """Get cached model data, refresh if needed
         
         Args:
             force_refresh: Whether to refresh the cache
             rebuild_cache: Whether to completely rebuild the cache
+            scope: Restrict an incremental reconcile to some roots / a folder
+                (ignored by a full rebuild, which always walks everything)
         """
         # If cache is not initialized, return an empty cache
         # Actual initialization should be done via initialize_in_background
@@ -1353,12 +1559,55 @@ class ModelScanner:
         # If force refresh is requested, initialize the cache directly
         if force_refresh:
             if rebuild_cache:
+                self._last_reconcile_summary = None
                 await self._initialize_cache()
             else:
-                await self._reconcile_cache()
+                self._last_reconcile_summary = await self._reconcile_cache(scope=scope)
         
         return cast(ModelCache, self._cache)
 
+    @property
+    def last_reconcile_summary(self) -> Optional[Dict[str, Any]]:
+        """Summary of the most recent incremental reconcile (None otherwise).
+
+        Carries the counts the refresh toast reports (added / removed /
+        repaired) plus the scan scope and the paths that were left untouched
+        because they were unreachable.
+        """
+        return self._last_reconcile_summary
+
+    def describe_model_roots(self) -> List[Dict[str, Any]]:
+        """Describe the configured roots for the refresh scope menu.
+
+        ``models`` is the cached entry count per root (the same attribution the
+        walk-progress weights use) and ``reachable`` is a live filesystem check,
+        so a switched-off drive shows as offline without touching the cache.
+        """
+        roots: List[str] = []
+        seen: Set[str] = set()
+        for root in self.get_model_roots():
+            if not root or root in seen:
+                continue
+            seen.add(root)
+            roots.append(root)
+
+        labels = _root_display_labels(roots)
+        cached_paths = (
+            {item.get('file_path', '') for item in self._cache.raw_data}
+            if self._cache is not None
+            else set()
+        )
+        counts = _count_cached_entries_per_root(cached_paths, roots)
+        return [
+            {
+                'path': root.replace(os.sep, '/'),
+                'label': labels[root],
+                'reachable': os.path.exists(root),
+                'models': counts.get(root, 0),
+            }
+            for root in roots
+        ]
+
     async def _initialize_cache(self) -> None:
         """Initialize or refresh the cache"""
         self._is_initializing = True  # Set flag
@@ -1450,8 +1699,15 @@ class ModelScanner:
         finally:
             self._is_initializing = False # Unset flag
 
-    async def _reconcile_cache(self) -> None:
-        """Fast cache reconciliation - only process differences between cache and filesystem"""
+    async def _reconcile_cache(self, scope: Optional[ReconcileScope] = None) -> Optional[Dict[str, Any]]:
+        """Fast cache reconciliation - only process differences between cache and filesystem.
+
+        ``scope`` restricts the reconcile to some of the configured roots and/or
+        a folder inside them: entries outside the scope are neither re-read nor
+        removed, so scanning one drive can never touch another. Paths the walk
+        could not read are kept and reported instead of being treated as
+        deleted. Returns a summary of the run (also broadcast to the UI).
+        """
         self.reset_cancellation()
         self._is_initializing = True # Set flag for reconciliation duration
         try:
@@ -1465,30 +1721,69 @@ class ModelScanner:
             cached_paths = {item['file_path'] for item in self._cache.raw_data}
             path_to_item = {item['file_path']: item for item in self._cache.raw_data}
 
-            # Every configured root that is currently reachable. A root that is
-            # missing (drive switched off, unmounted share) is skipped, so its
-            # cached entries are reported as missing below.
-            roots: List[str] = []
+            # Snapshot the configured roots once for this phase: scope
+            # resolution, reachability, symlink relevance and the new-file pass
+            # all read from this list.
+            configured_roots: List[str] = []
             seen_roots: Set[str] = set()
             for root_path in self.get_model_roots():
                 if not root_path or root_path in seen_roots:
                     continue
-                if not os.path.exists(root_path):
-                    continue
                 seen_roots.add(root_path)
+                configured_roots.append(root_path)
+
+            all_labels = _root_display_labels(configured_roots)
+            scope_roots = [
+                root for root in configured_roots
+                if scope is None or scope.roots is None or root in scope.roots
+            ]
+            scope_folder = scope.folder if scope is not None else None
+
+            # A configured root that is not reachable (drive switched off,
+            # unmounted share) is skipped instead of being treated as deleted.
+            unreachable = _UnreachablePaths()
+            roots: List[str] = []
+            skipped_roots: List[Dict[str, Any]] = []
+            for root_path in scope_roots:
+                if not os.path.exists(root_path):
+                    unreachable.add(root_path, 'root_unreachable')
+                    skipped_roots.append({
+                        'path': root_path.replace(os.sep, '/'),
+                        'label': all_labels.get(root_path, root_path),
+                        'reason': 'root_unreachable',
+                    })
+                    continue
                 roots.append(root_path)
 
+            self._collect_offline_symlink_prefixes(roots, unreachable)
+
+            # Scope prefixes come from every root the caller asked for (even the
+            # unreachable ones) so their entries are recognised as "in scope but
+            # unreadable" and reported instead of silently disappearing.
+            scope_prefixes = [
+                (root, _scope_prefix(root, scope_folder)) for root in scope_roots
+            ]
+            walk_prefixes = [
+                (root, _scope_prefix(root, scope_folder)) for root in roots
+            ]
+
             # Roots on different devices are walked by parallel workers (a cold
             # or slow drive then no longer serializes the others); roots sharing
             # a device stay sequential so directory claims remain deterministic.
             tracker = _ReconcileWalkTracker(
-                roots, _count_cached_entries_per_root(cached_paths, roots)
+                roots,
+                _count_cached_entries_for_prefixes(cached_paths, walk_prefixes),
+                labels={root: all_labels.get(root, root) for root in roots},
             )
             walk_results = await self._walk_roots_for_reconcile(
                 roots=roots,
+                walk_targets={
+                    root: _scope_walk_path(root, scope_folder) for root in roots
+                },
                 tracker=tracker,
                 cached_paths=cached_paths,
                 path_to_item=path_to_item,
+                unreachable=unreachable,
             )
 
             # Final walk snapshot: the bar reaches the walk share, then the
@@ -1675,8 +1970,21 @@ class ModelScanner:
                             exc,
                         )
 
-            # Find missing files (in cache but not in filesystem)
-            missing_files = cached_paths - found_paths
+            # Find missing files (in cache but not in filesystem). Only paths
+            # inside this scan's scope are candidates, and paths the walk could
+            # not read are kept and reported instead of being removed.
+            missing_files: Set[str] = set()
+            for path in cached_paths - found_paths:
+                if not any(
+                    _path_matches_prefix(path, prefix)
+                    for _root, prefix in scope_prefixes
+                ):
+                    continue
+                unreachable_prefix = unreachable.match(path)
+                if unreachable_prefix is not None:
+                    unreachable.record_kept(unreachable_prefix)
+                    continue
+                missing_files.add(path)
             total_removed = 0
             
             if missing_files:
@@ -1732,13 +2040,28 @@ class ModelScanner:
                     self._cache.raw_data = list(reversed(deduped))
                     total_removed += dedup_removed
             
-            # The walk above visited every directory, so refresh the recorded
-            # folder list (including empty folders) even when no model files
-            # changed — e.g. an empty folder was created or removed externally.
+            # The walk above visited every directory *in scope*, so refresh the
+            # recorded folder list (including empty folders) when nothing was
+            # left unverified — e.g. an empty folder was created or removed
+            # externally. A scoped scan, or one with unreadable paths, can only
+            # add to the list: dropping folders this walk never looked at would
+            # empty the sidebar for every drive that was not scanned.
             sorted_discovered = sorted(discovered_folders, key=lambda x: x.lower())
-            folders_changed = self._cache.all_folders != sorted_discovered
+            fully_verified = (
+                len(roots) == len(configured_roots)
+                and scope_folder is None
+                and not unreachable.has_entries()
+            )
+            if fully_verified:
+                merged_folders = sorted_discovered
+            else:
+                merged_folders = sorted(
+                    set(self._cache.all_folders or []) | set(sorted_discovered),
+                    key=lambda x: x.lower(),
+                )
+            folders_changed = self._cache.all_folders != merged_folders
             if folders_changed:
-                self._cache.all_folders = sorted_discovered
+                self._cache.all_folders = merged_folders
 
             # Resort cache if changes were made
             if total_added > 0 or total_removed > 0:
@@ -1755,16 +2078,33 @@ class ModelScanner:
             elif folders_changed:
                 await self._persist_current_cache()
                 
+            summary: Dict[str, Any] = {
+                'added': total_added,
+                'removed': total_removed,
+                'repaired': total_repaired,
+                'scanned_roots': [all_labels.get(root, root) for root in roots],
+                'skipped_roots': skipped_roots,
+                'unavailable_paths': unreachable.payload(),
+                'unavailable_paths_total': unreachable.count(),
+                'kept_unreachable': unreachable.total_kept(),
+            }
             logger.info(
                 f"{self.model_type.capitalize()} Scanner: Cache reconciliation completed in "
                 f"{time.time() - start_time:.2f} seconds. Added {total_added}, "
                 f"removed {total_removed}, repaired {total_repaired} models."
+                + (
+                    f" Skipped {len(skipped_roots)} unreachable root(s), kept "
+                    f"{summary['kept_unreachable']} model(s) under unreadable paths."
+                    if skipped_roots or unreachable.has_entries()
+                    else ""
+                )
             )
             await self._broadcast_scan_progress(
                 'completed', 'process_new', 100, False,
-                added=total_added, removed=total_removed,
                 elapsed_seconds=time.time() - start_time,
+                **summary,
             )
+            return summary
         except Exception as e:
             logger.error(f"{self.model_type.capitalize()} Scanner: Error reconciling cache: {e}", exc_info=True)
             await self._broadcast_scan_progress(
@@ -1779,9 +2119,11 @@ class ModelScanner:
         self,
         *,
         roots: List[str],
+        walk_targets: Mapping[str, str],
         tracker: _ReconcileWalkTracker,
         cached_paths: Set[str],
         path_to_item: Mapping[str, Dict[str, Any]],
+        unreachable: _UnreachablePaths,
     ) -> List[_RootWalkResult]:
         """Walk every root off the event loop and return results in root order.
 
@@ -1810,6 +2152,8 @@ class ModelScanner:
                     dir_claims,
                     excluded_models,
                     path_to_item,
+                    walk_targets,
+                    unreachable,
                 )
                 for group in _group_roots_by_device(roots)
             ]
@@ -1837,6 +2181,8 @@ class ModelScanner:
         dir_claims: _RealDirClaims,
         excluded_models: Set[str],
         path_to_item: Mapping[str, Dict[str, Any]],
+        walk_targets: Mapping[str, str],
+        unreachable: _UnreachablePaths,
     ) -> List[_RootWalkResult]:
         """Walk the roots of one device sequentially (worker-thread entry point)."""
         results: List[_RootWalkResult] = []
@@ -1852,6 +2198,7 @@ class ModelScanner:
             try:
                 result = _walk_root_for_reconcile(
                     root_path=root_path,
+                    walk_path=walk_targets.get(root_path, root_path),
                     file_extensions=self.file_extensions,
                     cached_paths=lookups.cached_paths,
                     path_to_item=path_to_item,
@@ -1860,6 +2207,7 @@ class ModelScanner:
                     excluded_models=excluded_models,
                     is_cancelled=self.is_cancelled,
                     report_progress=report_progress,
+                    unreachable=unreachable,
                 )
             finally:
                 tracker.finish_root(root_path)
@@ -1869,6 +2217,41 @@ class ModelScanner:
                 break
         return results
 
+    def _collect_offline_symlink_prefixes(
+        self, roots: Sequence[str], unreachable: _UnreachablePaths
+    ) -> None:
+        """Flag known first-level symlinks whose target is not a directory.
+
+        ``config`` deliberately tracks only symlinks directly under a root (see
+        ``Config._scan_symbolic_links``), so this costs one ``isdir`` per known
+        mapping and covers "the linked drive is switched off" for the layouts the
+        scanner already knows about. Nested symlinks stay out of scope.
+        """
+        try:
+            mappings = config.iter_path_mappings()
+        except Exception as exc:  # pragma: no cover - defensive logging
+            logger.debug(
+                "%s Scanner: symlink map unavailable: %s",
+                self.model_type.capitalize(),
+                exc,
+            )
+            return
+        if not mappings or not roots:
+            return
+
+        root_prefixes = [_normalized_root_prefix(root) for root in roots]
+        for target, link in mappings:
+            link_prefix = _normalized_root_prefix(link)
+            if not any(
+                link_prefix == root_prefix
+                or _path_matches_prefix(link_prefix, root_prefix)
+                for root_prefix in root_prefixes
+            ):
+                continue
+            if os.path.isdir(target):
+                continue
+            unreachable.add(link, 'symlink_target_offline')
+
     async def _monitor_walk_progress(self, tracker: _ReconcileWalkTracker) -> None:
         """Broadcast walk progress while the root workers are running."""
         while True:
diff --git a/static/css/layout.css b/static/css/layout.css
index 5e0ed103..c28d191b 100644
--- a/static/css/layout.css
+++ b/static/css/layout.css
@@ -700,3 +700,48 @@ body.sticky-controls .sticky-topbar {
         padding: 10px 0;
     }
 }
+
+/* Refresh dropdown: per-root scan scope (issue #1108). The list can hold one
+   entry per configured model root, so it scrolls instead of growing past the
+   viewport. Offline roots stay clickable (clicking explains the state) and are
+   only visually de-emphasised — unlike .dropdown-item.disabled, which swallows
+   the click via pointer-events: none. */
+.dropdown-separator {
+    height: 1px;
+    margin: 5px 0;
+    background-color: var(--border-color);
+}
+
+.dropdown-section-title {
+    padding: 4px 15px 2px;
+    font-size: 0.85em;
+    font-weight: 600;
+    color: var(--text-color);
+    opacity: 0.6;
+}
+
+.dropdown-scope-list {
+    max-height: 45vh;
+    overflow-y: auto;
+}
+
+.scan-root-item.is-offline {
+    cursor: default;
+    opacity: 0.6;
+}
+
+.scan-root-label {
+    margin-right: 12px;
+}
+
+.scan-root-count,
+.scan-root-offline {
+    float: right;
+    margin-left: 16px;
+    font-size: 0.9em;
+    opacity: 0.7;
+}
+
+.scan-root-item.is-offline .scan-root-offline {
+    opacity: 0.9;
+}
diff --git a/static/js/api/baseModelApi.js b/static/js/api/baseModelApi.js
index cce6ffa3..e00f8494 100644
--- a/static/js/api/baseModelApi.js
+++ b/static/js/api/baseModelApi.js
@@ -511,8 +511,9 @@ export class BaseModelApiClient {
         }
     }
 
-    async refreshModels(fullRebuild = false) {
+    async refreshModels(fullRebuild = false, { roots = null } = {}) {
         const abortController = new AbortController();
+        const scopeRoots = Array.isArray(roots) ? roots.filter(Boolean) : [];
         const displayName = this.apiConfig.config.displayName;
         const singularName = this.apiConfig.config.singularName;
         const actionText = translate(
@@ -600,6 +601,9 @@ export class BaseModelApiClient {
 
             const url = new URL(this.apiConfig.endpoints.scan, window.location.origin);
             url.searchParams.append('full_rebuild', fullRebuild);
+            for (const root of scopeRoots) {
+                url.searchParams.append('roots', root);
+            }
 
             const response = await fetch(url, { signal: abortController.signal });
 
@@ -615,7 +619,7 @@ export class BaseModelApiClient {
 
             resetAndReload(true);
 
-            showToast('toast.api.refreshComplete', { action: actionText }, 'success');
+            this._showRefreshSummary(data, actionText, scopeRoots);
         } catch (error) {
             if (error.name === 'AbortError') {
                 showToast('toast.api.operationCancelled', {}, 'info');
@@ -632,6 +636,59 @@ export class BaseModelApiClient {
         }
     }
 
+    /**
+     * Report what a finished scan did.
+     *
+     * A scoped scan names the folder it scanned and how many models changed; a
+     * scan that could not read part of its scope says so instead of silently
+     * looking like "nothing found" (the entries are kept, not deleted).
+     * @param {Object} summary - Scan response payload
+     * @param {string} actionText - Localized "Refresh" / "Full rebuild"
+     * @param {Array<string>} scopeRoots - Roots the scan was restricted to
+     */
+    _showRefreshSummary(summary, actionText, scopeRoots = []) {
+        const payload = summary || {};
+        const scannedRoots = Array.isArray(payload.scanned_roots) ? payload.scanned_roots : [];
+        const scopeLabel = scannedRoots.length ? scannedRoots.join(', ') : '';
+
+        if (scopeRoots.length && scopeLabel) {
+            showToast(
+                'toast.api.refreshCompleteScoped',
+                {
+                    scope: scopeLabel,
+                    added: Number(payload.added || 0),
+                    removed: Number(payload.removed || 0),
+                },
+                'success'
+            );
+        } else {
+            showToast('toast.api.refreshComplete', { action: actionText }, 'success');
+        }
+
+        const keptCount = Number(payload.kept_unreachable || 0);
+        if (keptCount > 0) {
+            const unavailable = Array.isArray(payload.unavailable_paths)
+                ? payload.unavailable_paths
+                : [];
+            const skipped = Array.isArray(payload.skipped_roots) ? payload.skipped_roots : [];
+            // Skipped roots already carry a short label; the remaining
+            // unreadable folders only have a path.
+            const names = (
+                skipped.length
+                    ? skipped.map(entry => entry?.label || entry?.path)
+                    : unavailable.map(entry => entry?.path)
+            ).filter(Boolean);
+            showToast(
+                'toast.api.refreshKeptUnreachable',
+                {
+                    count: keptCount.toLocaleString(),
+                    paths: names.slice(0, 3).join(', ') || '—',
+                },
+                'info'
+            );
+        }
+    }
+
     /**
      * Connect to the shared fetch-progress WebSocket for scan progress updates.
      * Returns null when the connection cannot be established (silent fallback).
diff --git a/static/js/components/controls/CheckpointsControls.js b/static/js/components/controls/CheckpointsControls.js
index 51473c31..4e65b57a 100644
--- a/static/js/components/controls/CheckpointsControls.js
+++ b/static/js/components/controls/CheckpointsControls.js
@@ -33,9 +33,6 @@ export class CheckpointsControls extends PageControls {
                 return await resetAndReload(updateFolders);
             },
             
-            refreshModels: async (fullRebuild = false) => {
-                return await getModelApiClient().refreshModels(fullRebuild);
-            },
             
             // Add fetch from Civitai functionality for checkpoints
             fetchFromCivitai: async () => {
diff --git a/static/js/components/controls/EmbeddingsControls.js b/static/js/components/controls/EmbeddingsControls.js
index 6b8042df..4c200cba 100644
--- a/static/js/components/controls/EmbeddingsControls.js
+++ b/static/js/components/controls/EmbeddingsControls.js
@@ -30,9 +30,6 @@ export class EmbeddingsControls extends PageControls {
                 return await resetAndReload(updateFolders);
             },
             
-            refreshModels: async (fullRebuild = false) => {
-                return await getModelApiClient().refreshModels(fullRebuild);
-            },
             
             // Add fetch from Civitai functionality for embeddings
             fetchFromCivitai: async () => {
diff --git a/static/js/components/controls/LorasControls.js b/static/js/components/controls/LorasControls.js
index b79139ac..e54a11f8 100644
--- a/static/js/components/controls/LorasControls.js
+++ b/static/js/components/controls/LorasControls.js
@@ -37,9 +37,6 @@ export class LorasControls extends PageControls {
                 return await resetAndReload(updateFolders);
             },
             
-            refreshModels: async (fullRebuild = false) => {
-                return await getModelApiClient().refreshModels(fullRebuild);
-            },
             
             // LoRA-specific API functions
             fetchFromCivitai: async () => {
diff --git a/static/js/components/controls/OtherControls.js b/static/js/components/controls/OtherControls.js
index c9bb6d60..dae878ee 100644
--- a/static/js/components/controls/OtherControls.js
+++ b/static/js/components/controls/OtherControls.js
@@ -31,9 +31,6 @@ export class OtherControls extends PageControls {
                 return await resetAndReload(updateFolders);
             },
 
-            refreshModels: async (fullRebuild = false) => {
-                return await getModelApiClient().refreshModels(fullRebuild);
-            },
 
             // Add fetch from Civitai functionality for other models
             fetchFromCivitai: async () => {
diff --git a/static/js/components/controls/PageControls.js b/static/js/components/controls/PageControls.js
index 294651dd..089ad9c6 100644
--- a/static/js/components/controls/PageControls.js
+++ b/static/js/components/controls/PageControls.js
@@ -5,7 +5,9 @@ import { showToast, openCivitaiByMetadata, isTypingContext } from '../../utils/u
 import { eventManager } from '../../utils/EventManager.js';
 import { performModelUpdateCheck } from '../../utils/updateCheckHelpers.js';
 import { sidebarManager } from '../SidebarManager.js';
+import { getModelApiClient } from '../../api/modelApiFactory.js';
 import { initSortDropdown, applySortToSelect, randomizeSortValue } from './SortDropdown.js';
+import { renderScanScopeMenu, resolveScanScopeTarget } from './ScanScopeMenu.js';
 
 /**
  * PageControls class - Unified control management for model pages
@@ -82,7 +84,18 @@ export class PageControls {
      * @param {Object} api - API methods for the page
      */
     registerAPI(api) {
-        this.api = api;
+        this.api = {
+            ...api,
+            // These two are identical for every page and must stay in sync with
+            // the scan API: the refresh scope menu reads the root list, and a
+            // scoped refresh has to pass `roots` through. They are defined here
+            // rather than in each page facade so a page cannot silently drop
+            // them (which is exactly how the scope menu ended up empty).
+            fetchModelRoots: async () => getModelApiClient().fetchModelRoots(),
+            // Forward the exact arguments: an unscoped refresh must keep calling
+            // the client with a single argument.
+            refreshModels: async (...args) => getModelApiClient().refreshModels(...args),
+        };
         console.log(`API methods registered for ${this.pageType} page`);
         
         // Initialize sidebar manager after API is registered
@@ -233,7 +246,10 @@ export class PageControls {
                 });
                 
                 // Toggle current dropdown
-                dropdownGroup.classList.toggle('active');
+                const isOpen = dropdownGroup.classList.toggle('active');
+                if (isOpen) {
+                    this.loadScanScopeMenu();
+                }
             });
         });
         
@@ -248,6 +264,21 @@ export class PageControls {
             });
         }
 
+        // Per-root scan rows are rendered dynamically, so they are wired by
+        // delegation instead of a direct querySelector per item.
+        const scopeMenu = document.getElementById('refreshScopeMenu');
+        if (scopeMenu) {
+            scopeMenu.addEventListener('click', (e) => {
+                const item = e.target.closest('[data-action="scan-root"]');
+                if (!item) {
+                    return;
+                }
+                e.stopPropagation();
+                this.handleScanRootSelection(item);
+                document.querySelector('.dropdown-group.active')?.classList.remove('active');
+            });
+        }
+
         const checkUpdatesOption = document.getElementById('checkUpdatesMenuItem');
         if (checkUpdatesOption) {
             checkUpdatesOption.addEventListener('click', async (e) => {
@@ -266,6 +297,55 @@ export class PageControls {
         });
     }
 
+    /**
+     * Render the per-root scan entries of the refresh dropdown.
+     *
+     * Roots come from the backend (label, model count, reachability) so the menu
+     * always names a root exactly like the scan progress line does. The list is
+     * cached until the next scan finishes.
+     */
+    async loadScanScopeMenu() {
+        const menu = document.getElementById('refreshScopeMenu');
+        if (!menu || typeof this.api?.fetchModelRoots !== 'function') {
+            return;
+        }
+
+        if (this._scanScopeDetails) {
+            this.renderScanScopeMenu(this._scanScopeDetails);
+            return;
+        }
+        if (this._scanScopeLoading) {
+            return;
+        }
+
+        this._scanScopeLoading = true;
+        try {
+            const payload = await this.api.fetchModelRoots();
+            const details = Array.isArray(payload?.root_details) ? payload.root_details : [];
+            this._scanScopeDetails = details;
+            renderScanScopeMenu(menu, details);
+        } catch (error) {
+            console.error('Error loading model roots:', error);
+            menu.innerHTML = '';
+        } finally {
+            this._scanScopeLoading = false;
+        }
+    }
+
+    handleScanRootSelection(item) {
+        const { rootPath, label, offline } = resolveScanScopeTarget(item);
+        if (!rootPath) {
+            return;
+        }
+        if (offline) {
+            // showToast(key, params, type): the sentence must NOT be passed here,
+            // it used to land in the `type` slot and produced an unstyled toast.
+            showToast('toast.api.scanRootUnreachable', { scope: label }, 'info');
+            return;
+        }
+        this.refreshModels(false, { roots: [rootPath] });
+    }
+
     async handleCheckModelUpdates(menuItem) {
         if (this._updateCheckInProgress) {
             return;
@@ -482,14 +562,23 @@ export class PageControls {
      * Refresh models list
      * @param {boolean} fullRebuild - Whether to perform a full rebuild
      */
-    async refreshModels(fullRebuild = false) {
+    async refreshModels(fullRebuild = false, { roots = null } = {}) {
         if (!this.api) {
             console.error('API methods not registered');
             return;
         }
 
+        // Root labels / reachability may have changed with the scan, and the
+        // model counts definitely did.
+        this._scanScopeDetails = null;
+        const scopedRoots = Array.isArray(roots) ? roots.filter(Boolean) : [];
+
         try {
-            await this.api.refreshModels(fullRebuild);
+            if (scopedRoots.length) {
+                await this.api.refreshModels(fullRebuild, { roots: scopedRoots });
+            } else {
+                await this.api.refreshModels(fullRebuild);
+            }
             
             // Refresh sidebar after rebuild
             if (this.sidebarManager) {
diff --git a/static/js/components/controls/ScanScopeMenu.js b/static/js/components/controls/ScanScopeMenu.js
new file mode 100644
index 00000000..8b03cf94
--- /dev/null
+++ b/static/js/components/controls/ScanScopeMenu.js
@@ -0,0 +1,72 @@
+// ScanScopeMenu.js - per-root entries of the Refresh dropdown (issue #1108)
+import { translate } from '../../utils/i18nHelpers.js';
+
+/**
+ * Render one row per configured model root.
+ *
+ * Rows carry the root path in `data-root` and are wired by delegation, because
+ * the list is rebuilt every time the root set changes. An offline root stays
+ * clickable (the click explains why nothing can be scanned) and is only
+ * de-emphasised visually.
+ *
+ * @param {HTMLElement|null} menu - Container element (#refreshScopeMenu)
+ * @param {Array<Object>} details - `root_details` from GET /api/lm/{type}/roots
+ */
+export function renderScanScopeMenu(menu, details = []) {
+    if (!menu) {
+        return;
+    }
+    menu.innerHTML = '';
+
+    details.forEach(detail => {
+        if (!detail || !detail.path) {
+            return;
+        }
+        const item = document.createElement('div');
+        item.className = `dropdown-item scan-root-item${detail.reachable ? '' : ' is-offline'}`;
+        item.dataset.action = 'scan-root';
+        item.dataset.root = detail.path;
+        item.title = detail.path;
+
+        const icon = document.createElement('i');
+        icon.className = `fas ${detail.reachable ? 'fa-folder-open' : 'fa-plug-circle-xmark'}`;
+        item.appendChild(icon);
+
+        const label = document.createElement('span');
+        label.className = 'scan-root-label';
+        label.textContent = detail.label || detail.path;
+        item.appendChild(label);
+
+        const meta = document.createElement('span');
+        if (detail.reachable) {
+            const count = Number(detail.models || 0).toLocaleString();
+            meta.className = 'scan-root-count';
+            meta.textContent = translate(
+                'loras.controls.refresh.rootModels',
+                { count },
+                `${count} models`
+            );
+        } else {
+            meta.className = 'scan-root-offline';
+            meta.textContent = translate('loras.controls.refresh.rootOffline', {}, 'Offline');
+        }
+        item.appendChild(meta);
+
+        menu.appendChild(item);
+    });
+}
+
+/**
+ * Read what a clicked row refers to.
+ * @param {HTMLElement} item - Row rendered by renderScanScopeMenu
+ * @returns {{rootPath: string, label: string, offline: boolean}}
+ */
+export function resolveScanScopeTarget(item) {
+    const rootPath = item?.dataset?.root || '';
+    const label = item?.querySelector?.('.scan-root-label')?.textContent || rootPath;
+    return {
+        rootPath,
+        label,
+        offline: Boolean(item?.classList?.contains('is-offline')),
+    };
+}
diff --git a/static/js/utils/uiHelpers.js b/static/js/utils/uiHelpers.js
index 1f932b8c..278f70e6 100644
--- a/static/js/utils/uiHelpers.js
+++ b/static/js/utils/uiHelpers.js
@@ -139,9 +139,14 @@ export async function copyToClipboard(text, successMessage = null) {
  * @param {string} type - Toast type (info/success/warning/error)
  * @returns {HTMLElement} The toast element (not yet attached to the DOM)
  */
+// Only these carry styling (icon + accent border). An unknown type is coerced
+// to `info` instead of ending up as a bare `.toast` box — a wrong argument
+// order at a call site used to leak the message itself into the class list.
+const TOAST_TYPES = new Set(['info', 'success', 'warning', 'error', 'copy']);
+
 function createToastElement(message, type) {
   const toast = document.createElement('div');
-  toast.className = `toast toast-${type}`;
+  toast.className = `toast toast-${TOAST_TYPES.has(type) ? type : 'info'}`;
   toast.textContent = message;
   return toast;
 }
diff --git a/templates/components/controls.html b/templates/components/controls.html
index b542371d..997d6b95 100644
--- a/templates/components/controls.html
+++ b/templates/components/controls.html
@@ -73,6 +73,12 @@
                     <div class="dropdown-item" data-action="full-rebuild" title="{% if page_id == 'recipes' %}{{ t('recipes.controls.refresh.fullTooltip', default='Rebuild cache - full rescan of all recipe files') }}{% else %}{{ t('loras.controls.refresh.fullTooltip') }}{% endif %}">
                         <i class="fas fa-tools"></i> <span>{% if page_id == 'recipes' %}{{ t('loras.controls.refresh.full', default='Rebuild Cache') }}{% else %}{{ t('loras.controls.refresh.full') }}{% endif %}</span>
                     </div>
+                    {% if page_id != 'recipes' %}
+                    <!-- Per-root scan scope, filled by PageControls.loadScanScopeMenu() -->
+                    <div class="dropdown-separator"></div>
+                    <div class="dropdown-section-title">{{ t('loras.controls.refresh.scopeSection') }}</div>
+                    <div id="refreshScopeMenu" class="dropdown-scope-list"></div>
+                    {% endif %}
                 </div>
             </div>
             
diff --git a/tests/frontend/api/baseModelApi.refresh.test.js b/tests/frontend/api/baseModelApi.refresh.test.js
index 55724efe..4d4a29d5 100644
--- a/tests/frontend/api/baseModelApi.refresh.test.js
+++ b/tests/frontend/api/baseModelApi.refresh.test.js
@@ -153,8 +153,8 @@ describe('BaseModelApiClient.refreshModels scan progress', () => {
     };
   }
 
-  async function startRefresh(client, fullRebuild = false) {
-    const promise = client.refreshModels(fullRebuild);
+  async function startRefresh(client, fullRebuild = false, options = {}) {
+    const promise = client.refreshModels(fullRebuild, options);
     await vi.waitFor(() => {
       expect(FakeWebSocket.instances.length).toBe(1);
     });
@@ -392,6 +392,75 @@ describe('BaseModelApiClient.refreshModels scan progress', () => {
     await promise;
   });
 
+  it('requests a scoped scan when roots are passed', async () => {
+    global.fetch = vi.fn().mockResolvedValue({
+      ok: true,
+      json: async () => ({ status: 'success' }),
+    });
+
+    const client = await createClient();
+    await client.refreshModels(false, { roots: ['/mnt/a/loras', '/mnt/b/loras'] });
+
+    const [url] = global.fetch.mock.calls[0];
+    expect(url.searchParams.getAll('roots')).toEqual(['/mnt/a/loras', '/mnt/b/loras']);
+    expect(url.searchParams.get('full_rebuild')).toBe('false');
+  });
+
+  it('reports the scoped scan summary and the entries kept unreachable', async () => {
+    const fetchControl = mockFetchPending();
+    const client = await createClient();
+    const { promise } = await startRefresh(client, false, { roots: ['/mnt/a/loras'] });
+
+    fetchControl.resolveOk({
+      status: 'success',
+      scanned_roots: ['a/loras'],
+      added: 2,
+      removed: 1,
+      kept_unreachable: 5,
+      unavailable_paths: [
+        { path: '/mnt/g/loras', reason: 'root_unreachable', kept: 5 },
+      ],
+      skipped_roots: [{ path: '/mnt/g/loras', label: 'g/loras' }],
+    });
+    await promise;
+
+    expect(showToastMock).toHaveBeenCalledWith(
+      'toast.api.refreshCompleteScoped',
+      { scope: 'a/loras', added: 2, removed: 1 },
+      'success'
+    );
+    expect(showToastMock).toHaveBeenCalledWith(
+      'toast.api.refreshKeptUnreachable',
+      { count: '5', paths: 'g/loras' },
+      'info'
+    );
+  });
+
+  it('keeps the generic completion toast for a full-library scan', async () => {
+    const fetchControl = mockFetchPending();
+    const client = await createClient();
+    const { promise } = await startRefresh(client);
+
+    fetchControl.resolveOk({
+      status: 'success',
+      scanned_roots: ['a/loras', 'b/loras'],
+      added: 0,
+      removed: 0,
+    });
+    await promise;
+
+    expect(showToastMock).toHaveBeenCalledWith(
+      'toast.api.refreshComplete',
+      { action: 'Refresh' },
+      'success'
+    );
+    expect(showToastMock).not.toHaveBeenCalledWith(
+      'toast.api.refreshCompleteScoped',
+      expect.anything(),
+      expect.anything()
+    );
+  });
+
   it('shows the cancelled toast when the server reports cancellation', async () => {
     const fetchControl = mockFetchPending();
     const client = await createClient();
diff --git a/tests/frontend/components/controls/pageControls.scanScope.test.js b/tests/frontend/components/controls/pageControls.scanScope.test.js
new file mode 100644
index 00000000..a636b975
--- /dev/null
+++ b/tests/frontend/components/controls/pageControls.scanScope.test.js
@@ -0,0 +1,236 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import { readFileSync } from 'fs';
+import path from 'path';
+
+const {
+  PAGE_CONTROLS_MODULE,
+  STATE_MODULE,
+  STORAGE_MODULE,
+  UI_HELPERS_MODULE,
+  EVENT_MANAGER_MODULE,
+  UPDATE_CHECK_MODULE,
+  SIDEBAR_MODULE,
+  SORT_DROPDOWN_MODULE,
+  API_FACTORY_MODULE,
+  I18N_MODULE,
+} = vi.hoisted(() => ({
+  PAGE_CONTROLS_MODULE: new URL('../../../../static/js/components/controls/PageControls.js', import.meta.url).pathname,
+  STATE_MODULE: new URL('../../../../static/js/state/index.js', import.meta.url).pathname,
+  STORAGE_MODULE: new URL('../../../../static/js/utils/storageHelpers.js', import.meta.url).pathname,
+  UI_HELPERS_MODULE: new URL('../../../../static/js/utils/uiHelpers.js', import.meta.url).pathname,
+  EVENT_MANAGER_MODULE: new URL('../../../../static/js/utils/EventManager.js', import.meta.url).pathname,
+  UPDATE_CHECK_MODULE: new URL('../../../../static/js/utils/updateCheckHelpers.js', import.meta.url).pathname,
+  SIDEBAR_MODULE: new URL('../../../../static/js/components/SidebarManager.js', import.meta.url).pathname,
+  SORT_DROPDOWN_MODULE: new URL('../../../../static/js/components/controls/SortDropdown.js', import.meta.url).pathname,
+  API_FACTORY_MODULE: new URL('../../../../static/js/api/modelApiFactory.js', import.meta.url).pathname,
+  I18N_MODULE: new URL('../../../../static/js/utils/i18nHelpers.js', import.meta.url).pathname,
+}));
+
+const CONTROLS_TEMPLATE = path.resolve(
+  __dirname,
+  '../../../../templates/components/controls.html'
+);
+
+const showToastMock = vi.fn();
+const modelClient = {
+  fetchModelRoots: vi.fn(),
+  refreshModels: vi.fn(),
+};
+
+vi.mock(STATE_MODULE, () => ({
+  state: {},
+  getCurrentPageState: vi.fn(() => ({ filters: {} })),
+  setCurrentPageType: vi.fn(),
+}));
+
+vi.mock(STORAGE_MODULE, () => ({
+  getStorageItem: vi.fn(),
+  setStorageItem: vi.fn(),
+  removeStorageItem: vi.fn(),
+  getSessionItem: vi.fn(),
+  setSessionItem: vi.fn(),
+  removeSessionItem: vi.fn(),
+}));
+
+vi.mock(UI_HELPERS_MODULE, () => ({
+  showToast: showToastMock,
+  openCivitaiByMetadata: vi.fn(),
+  isTypingContext: vi.fn(() => false),
+}));
+
+vi.mock(EVENT_MANAGER_MODULE, () => ({
+  eventManager: { on: vi.fn(), off: vi.fn(), emit: vi.fn() },
+}));
+
+vi.mock(UPDATE_CHECK_MODULE, () => ({
+  performModelUpdateCheck: vi.fn(),
+}));
+
+vi.mock(SIDEBAR_MODULE, () => ({
+  sidebarManager: {
+    setHostPageControls: vi.fn(),
+    initialize: vi.fn(async () => {}),
+    refresh: vi.fn(async () => {}),
+  },
+}));
+
+vi.mock(SORT_DROPDOWN_MODULE, () => ({
+  initSortDropdown: vi.fn(),
+  applySortToSelect: vi.fn(),
+  randomizeSortValue: vi.fn(),
+}));
+
+vi.mock(API_FACTORY_MODULE, () => ({
+  getModelApiClient: () => modelClient,
+}));
+
+vi.mock(I18N_MODULE, () => ({
+  translate: vi.fn((key, params, fallback) => {
+    if (!fallback) {
+      return key;
+    }
+    return Object.entries(params || {}).reduce(
+      (text, [name, value]) => text.replaceAll(`{${name}}`, value),
+      fallback
+    );
+  }),
+}));
+
+const { PageControls } = await import(PAGE_CONTROLS_MODULE);
+
+const ROOT_DETAILS = [
+  { path: '/mnt/a/loras', label: 'a/loras', reachable: true, models: 12 },
+  { path: '/mnt/b/loras', label: 'b/loras', reachable: false, models: 3 },
+];
+
+function buildControlsDom() {
+  document.body.innerHTML = `
+    <div class="dropdown-group">
+      <button data-action="refresh" class="dropdown-main"></button>
+      <button class="dropdown-toggle"></button>
+      <div class="dropdown-menu">
+        <div class="dropdown-item" data-action="full-rebuild"></div>
+        <div class="dropdown-separator"></div>
+        <div class="dropdown-section-title">Scan one folder</div>
+        <div id="refreshScopeMenu" class="dropdown-scope-list"></div>
+      </div>
+    </div>`;
+}
+
+function bareControls(api = {}) {
+  const controls = Object.create(PageControls.prototype);
+  controls.pageType = 'loras';
+  controls.api = api;
+  controls._scanScopeDetails = null;
+  controls._scanScopeLoading = false;
+  controls.refreshModels = vi.fn();
+  controls.sidebarManager = {
+    setHostPageControls: vi.fn(),
+    initialize: vi.fn(async () => {}),
+  };
+  return controls;
+}
+
+describe('PageControls refresh scope menu', () => {
+  beforeEach(() => {
+    showToastMock.mockReset();
+    modelClient.fetchModelRoots.mockReset();
+    modelClient.refreshModels.mockReset();
+    modelClient.fetchModelRoots.mockResolvedValue({ root_details: ROOT_DETAILS });
+  });
+
+  afterEach(() => {
+    document.body.innerHTML = '';
+  });
+
+  it('keeps the scope container in the controls template (non-recipes pages)', () => {
+    const html = readFileSync(CONTROLS_TEMPLATE, 'utf-8');
+    const rebuildIndex = html.indexOf('data-action="full-rebuild"');
+    const scopeIndex = html.indexOf('id="refreshScopeMenu"');
+
+    expect(rebuildIndex).toBeGreaterThan(-1);
+    // Same dropdown, after the rebuild entry.
+    expect(scopeIndex).toBeGreaterThan(rebuildIndex);
+    expect(html).toContain('loras.controls.refresh.scopeSection');
+    // The recipes page has no model roots, so the section is gated.
+    expect(html.slice(rebuildIndex, scopeIndex)).toContain("{% if page_id != 'recipes' %}");
+  });
+
+  it('registers the scan-scope API for every page through registerAPI', async () => {
+    const controls = bareControls();
+    controls.registerAPI({});
+
+    expect(typeof controls.api.fetchModelRoots).toBe('function');
+    expect(typeof controls.api.refreshModels).toBe('function');
+
+    await controls.api.fetchModelRoots();
+    expect(modelClient.fetchModelRoots).toHaveBeenCalled();
+
+    // The page facades used to drop the second argument, which silently turned
+    // a scoped scan into a full refresh.
+    await controls.api.refreshModels(false, { roots: ['/mnt/a/loras'] });
+    expect(modelClient.refreshModels).toHaveBeenCalledWith(false, { roots: ['/mnt/a/loras'] });
+  });
+
+  it('renders the root rows when the dropdown is opened', async () => {
+    buildControlsDom();
+    const controls = bareControls({
+      fetchModelRoots: vi.fn(async () => ({ root_details: ROOT_DETAILS })),
+      refreshModels: vi.fn(),
+    });
+
+    controls.initDropdowns();
+    document.querySelector('.dropdown-toggle').click();
+
+    await vi.waitFor(() => {
+      expect(document.querySelectorAll('.scan-root-item').length).toBe(2);
+    });
+    expect(document.querySelector('.scan-root-item').dataset.root).toBe('/mnt/a/loras');
+    expect(document.querySelector('.scan-root-count').textContent).toBe('12 models');
+    expect(document.querySelectorAll('.scan-root-item')[1].classList.contains('is-offline')).toBe(true);
+  });
+
+  it('scans the clicked root only', async () => {
+    buildControlsDom();
+    const controls = bareControls({
+      fetchModelRoots: vi.fn(async () => ({ root_details: ROOT_DETAILS })),
+      refreshModels: vi.fn(),
+    });
+
+    controls.initDropdowns();
+    document.querySelector('.dropdown-toggle').click();
+    await vi.waitFor(() => {
+      expect(document.querySelectorAll('.scan-root-item').length).toBe(2);
+    });
+
+    document.querySelectorAll('.scan-root-item')[0].click();
+
+    expect(controls.refreshModels).toHaveBeenCalledWith(false, { roots: ['/mnt/a/loras'] });
+    expect(showToastMock).not.toHaveBeenCalled();
+  });
+
+  it('explains an offline root instead of scanning it', async () => {
+    buildControlsDom();
+    const controls = bareControls({
+      fetchModelRoots: vi.fn(async () => ({ root_details: ROOT_DETAILS })),
+      refreshModels: vi.fn(),
+    });
+
+    controls.initDropdowns();
+    document.querySelector('.dropdown-toggle').click();
+    await vi.waitFor(() => {
+      expect(document.querySelectorAll('.scan-root-item').length).toBe(2);
+    });
+
+    document.querySelectorAll('.scan-root-item')[1].click();
+
+    expect(controls.refreshModels).not.toHaveBeenCalled();
+    // Exactly three arguments: key, params, type. A 4th "fallback" argument
+    // pushed the sentence into the type slot and rendered an unstyled toast.
+    expect(showToastMock).toHaveBeenCalledWith(
+      'toast.api.scanRootUnreachable',
+      { scope: 'b/loras' },
+      'info'
+    );
+  });
+});
diff --git a/tests/frontend/components/controls/scanScopeMenu.test.js b/tests/frontend/components/controls/scanScopeMenu.test.js
new file mode 100644
index 00000000..b5dac3a4
--- /dev/null
+++ b/tests/frontend/components/controls/scanScopeMenu.test.js
@@ -0,0 +1,77 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+const { I18N_MODULE, MODULE } = vi.hoisted(() => ({
+  I18N_MODULE: new URL('../../../../static/js/utils/i18nHelpers.js', import.meta.url).pathname,
+  MODULE: new URL('../../../../static/js/components/controls/ScanScopeMenu.js', import.meta.url).pathname,
+}));
+
+vi.mock(I18N_MODULE, () => ({
+  translate: vi.fn((key, params, fallback) => {
+    if (!fallback) {
+      return key;
+    }
+    return Object.entries(params || {}).reduce(
+      (text, [name, value]) => text.replaceAll(`{${name}}`, value),
+      fallback
+    );
+  }),
+}));
+
+const { renderScanScopeMenu, resolveScanScopeTarget } = await import(MODULE);
+
+describe('ScanScopeMenu', () => {
+  let menu;
+
+  beforeEach(() => {
+    document.body.innerHTML = '<div id="refreshScopeMenu"></div>';
+    menu = document.getElementById('refreshScopeMenu');
+  });
+
+  it('renders one row per root with label, count and offline state', () => {
+    renderScanScopeMenu(menu, [
+      { path: '/mnt/a/loras', label: 'a/loras', reachable: true, models: 7 },
+      { path: '/mnt/b/loras', label: 'b/loras', reachable: false, models: 0 },
+    ]);
+
+    const rows = menu.querySelectorAll('.scan-root-item');
+    expect(rows.length).toBe(2);
+
+    expect(rows[0].dataset.action).toBe('scan-root');
+    expect(rows[0].dataset.root).toBe('/mnt/a/loras');
+    expect(rows[0].title).toBe('/mnt/a/loras');
+    expect(rows[0].querySelector('.scan-root-label').textContent).toBe('a/loras');
+    expect(rows[0].querySelector('.scan-root-count').textContent).toBe('7 models');
+    expect(rows[0].classList.contains('is-offline')).toBe(false);
+
+    expect(rows[1].classList.contains('is-offline')).toBe(true);
+    expect(rows[1].querySelector('.scan-root-offline').textContent).toBe('Offline');
+    // Offline rows stay clickable so the click can explain the state.
+    expect(rows[1].dataset.action).toBe('scan-root');
+  });
+
+  it('resolveScanScopeTarget reads path, label and offline state', () => {
+    renderScanScopeMenu(menu, [
+      { path: '/mnt/b/loras', label: 'b/loras', reachable: false, models: 0 },
+    ]);
+
+    expect(resolveScanScopeTarget(menu.querySelector('.scan-root-item'))).toEqual({
+      rootPath: '/mnt/b/loras',
+      label: 'b/loras',
+      offline: true,
+    });
+  });
+
+  it('skips malformed entries and replaces the previous list', () => {
+    renderScanScopeMenu(menu, [{ path: '/mnt/a' }, null, {}]);
+    expect(menu.querySelectorAll('.scan-root-item').length).toBe(1);
+
+    renderScanScopeMenu(menu, []);
+    expect(menu.querySelectorAll('.scan-root-item').length).toBe(0);
+  });
+
+  it('falls back to the path when a root has no label', () => {
+    renderScanScopeMenu(menu, [{ path: '/mnt/a/loras', reachable: true, models: 0 }]);
+
+    expect(menu.querySelector('.scan-root-label').textContent).toBe('/mnt/a/loras');
+  });
+});
diff --git a/tests/frontend/utils/toastTypes.test.js b/tests/frontend/utils/toastTypes.test.js
new file mode 100644
index 00000000..509c6257
--- /dev/null
+++ b/tests/frontend/utils/toastTypes.test.js
@@ -0,0 +1,36 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+const { UI_HELPERS_MODULE, I18N_MODULE } = vi.hoisted(() => ({
+  UI_HELPERS_MODULE: new URL('../../../static/js/utils/uiHelpers.js', import.meta.url).pathname,
+  I18N_MODULE: new URL('../../../static/js/utils/i18nHelpers.js', import.meta.url).pathname,
+}));
+
+vi.mock(I18N_MODULE, () => ({
+  translate: vi.fn((key, params, fallback) => fallback || key),
+}));
+
+const { showToast } = await import(UI_HELPERS_MODULE);
+
+describe('toast type styling', () => {
+  beforeEach(() => {
+    document.body.innerHTML = '';
+  });
+
+  it('applies the requested type class', () => {
+    showToast('plain message', {}, 'success');
+    expect(document.querySelector('.toast').className).toBe('toast toast-success');
+  });
+
+  it('coerces an unknown type to info instead of rendering an unstyled toast', () => {
+    // Regression guard: a call site that passed its fallback sentence as the
+    // `type` produced `toast toast-drive-Z is not reachable ...`, which matched
+    // no rule at all (no icon, no accent border).
+    showToast('plain message', {}, 'drive-Z is not reachable right now');
+    expect(document.querySelector('.toast').className).toBe('toast toast-info');
+  });
+
+  it('defaults to info when no type is given', () => {
+    showToast('plain message');
+    expect(document.querySelector('.toast').className).toBe('toast toast-info');
+  });
+});
diff --git a/tests/routes/test_model_query_handler.py b/tests/routes/test_model_query_handler.py
index d3cd27a3..f333eea4 100644
--- a/tests/routes/test_model_query_handler.py
+++ b/tests/routes/test_model_query_handler.py
@@ -196,3 +196,126 @@ async def test_get_folder_tree_threads_include_empty():
 
     assert payload["success"] is True
     assert service.received_include_empty is True
+
+
+class QueryParams(dict):
+    """Minimal stand-in for aiohttp's MultiDict query (supports getall)."""
+
+    def getall(self, key, default=None):
+        value = self.get(key)
+        if value is None:
+            return list(default) if default else []
+        return value if isinstance(value, list) else [value]
+
+
+class ScopedScanService:
+    """Stub service recording the scan scope the handler resolves."""
+
+    model_type = "lora"
+
+    def __init__(self, roots=None, summary=None, cancelled=False):
+        self._roots = list(roots or [])
+        self._summary = summary
+        self.cancelled = cancelled
+        self.scanner = SimpleNamespace(is_cancelled=lambda: self.cancelled)
+        self.received_scope = "not-called"
+        self.received_rebuild = None
+
+    def get_model_roots(self):
+        return list(self._roots)
+
+    def describe_model_roots(self):
+        return [
+            {"path": root, "label": root.rsplit("/", 1)[-1], "reachable": True, "models": 7}
+            for root in self._roots
+        ]
+
+    async def scan_models(self, force_refresh=False, rebuild_cache=False, scope=None):
+        self.received_scope = scope
+        self.received_rebuild = rebuild_cache
+        return self._summary
+
+
+SUMMARY = {
+    "added": 3,
+    "removed": 0,
+    "repaired": 1,
+    "scanned_roots": ["a"],
+    "skipped_roots": [],
+    "unavailable_paths": [],
+    "unavailable_paths_total": 0,
+    "kept_unreachable": 0,
+}
+
+
+@pytest.mark.asyncio
+async def test_scan_models_accepts_roots_param():
+    service = ScopedScanService(roots=["/mnt/a", "/mnt/b"], summary=SUMMARY)
+    handler = ModelQueryHandler(service=service, logger=logging.getLogger(__name__))
+
+    response = await handler.scan_models(
+        SimpleNamespace(query=QueryParams({"roots": ["/mnt/a"]}))
+    )
+    payload = json.loads(response.text)
+
+    assert response.status == 200
+    assert payload["status"] == "success"
+    assert payload["added"] == 3
+    assert payload["scanned_roots"] == ["a"]
+    assert service.received_scope is not None
+    assert service.received_scope.roots == ("/mnt/a",)
+    assert service.received_rebuild is False
+
+
+@pytest.mark.asyncio
+async def test_scan_models_without_roots_scans_every_root():
+    service = ScopedScanService(roots=["/mnt/a"], summary=SUMMARY)
+    handler = ModelQueryHandler(service=service, logger=logging.getLogger(__name__))
+
+    await handler.scan_models(SimpleNamespace(query=QueryParams({})))
+
+    assert service.received_scope is None
+
+
+@pytest.mark.asyncio
+async def test_scan_models_rejects_unknown_root():
+    service = ScopedScanService(roots=["/mnt/a"], summary=SUMMARY)
+    handler = ModelQueryHandler(service=service, logger=logging.getLogger(__name__))
+
+    response = await handler.scan_models(
+        SimpleNamespace(query=QueryParams({"roots": ["/mnt/nope"]}))
+    )
+    payload = json.loads(response.text)
+
+    assert response.status == 400
+    assert payload["roots"] == ["/mnt/nope"]
+    assert service.received_scope == "not-called"
+
+
+@pytest.mark.asyncio
+async def test_scan_models_rejects_roots_with_full_rebuild():
+    service = ScopedScanService(roots=["/mnt/a"], summary=SUMMARY)
+    handler = ModelQueryHandler(service=service, logger=logging.getLogger(__name__))
+
+    response = await handler.scan_models(
+        SimpleNamespace(
+            query=QueryParams({"roots": ["/mnt/a"], "full_rebuild": "true"})
+        )
+    )
+
+    assert response.status == 400
+    assert service.received_scope == "not-called"
+
+
+@pytest.mark.asyncio
+async def test_get_model_roots_reports_details():
+    service = ScopedScanService(roots=["/mnt/a", "/mnt/b"])
+    handler = ModelQueryHandler(service=service, logger=logging.getLogger(__name__))
+
+    response = await handler.get_model_roots(SimpleNamespace(query=QueryParams({})))
+    payload = json.loads(response.text)
+
+    # `roots` stays a plain list of paths for the existing callers.
+    assert payload["roots"] == ["/mnt/a", "/mnt/b"]
+    assert [detail["label"] for detail in payload["root_details"]] == ["a", "b"]
+    assert all(detail["models"] == 7 for detail in payload["root_details"])
diff --git a/tests/routes/test_preview_routes.py b/tests/routes/test_preview_routes.py
index 6060cd21..569aff94 100644
--- a/tests/routes/test_preview_routes.py
+++ b/tests/routes/test_preview_routes.py
@@ -1,7 +1,8 @@
+import asyncio
 import os
 import urllib.parse
 from pathlib import Path
-from unittest.mock import patch
+from unittest.mock import AsyncMock, patch
 
 import pytest
 from aiohttp import web
@@ -348,3 +349,67 @@ async def test_deep_symlink_discovered_on_first_access(tmp_path):
 
     # Deep symlink should now be in mappings
     assert normalized_external in config._path_mappings
+
+
+async def test_preview_404_keeps_cache_when_parent_dir_missing(tmp_path):
+    """A preview whose directory is unreachable (drive off) must not clear the
+    cached preview_url: nothing was deleted, the file just cannot be read."""
+    library_root = tmp_path / "library"
+    library_root.mkdir()
+    unreachable_parent = library_root / "gone"
+    preview_path = unreachable_parent / "model.webp"
+
+    config = Config()
+    config.apply_library_settings(
+        {
+            "folder_paths": {
+                "loras": [str(library_root)],
+                "checkpoints": [],
+                "unet": [],
+                "embeddings": [],
+            }
+        }
+    )
+
+    handler = PreviewHandler(config=config)
+    encoded_path = urllib.parse.quote(str(preview_path), safe="")
+    request = make_mocked_request("GET", f"/api/lm/previews?path={encoded_path}")
+
+    with patch.object(handler, "_cleanup_stale_preview_url", new=AsyncMock()) as cleanup:
+        with pytest.raises(web.HTTPNotFound):
+            await handler.serve_preview(request)
+        await asyncio.sleep(0)
+
+    cleanup.assert_not_called()
+
+
+async def test_preview_404_clears_cache_when_file_really_deleted(tmp_path):
+    """A preview deleted from a reachable directory is genuinely stale."""
+    library_root = tmp_path / "library"
+    library_root.mkdir()
+    preview_path = library_root / "model.webp"
+    preview_path.write_bytes(b"preview")
+    preview_path.unlink()
+
+    config = Config()
+    config.apply_library_settings(
+        {
+            "folder_paths": {
+                "loras": [str(library_root)],
+                "checkpoints": [],
+                "unet": [],
+                "embeddings": [],
+            }
+        }
+    )
+
+    handler = PreviewHandler(config=config)
+    encoded_path = urllib.parse.quote(str(preview_path), safe="")
+    request = make_mocked_request("GET", f"/api/lm/previews?path={encoded_path}")
+
+    with patch.object(handler, "_cleanup_stale_preview_url", new=AsyncMock()) as cleanup:
+        with pytest.raises(web.HTTPNotFound):
+            await handler.serve_preview(request)
+        await asyncio.sleep(0)
+
+    cleanup.assert_awaited_once()
diff --git a/tests/services/test_model_scanner.py b/tests/services/test_model_scanner.py
index 19cdbc64..ae6f63bf 100644
--- a/tests/services/test_model_scanner.py
+++ b/tests/services/test_model_scanner.py
@@ -20,9 +20,11 @@ from py.services.model_hash_index import ModelHashIndex
 from py.services.model_scanner import (
     CacheBuildResult,
     ModelScanner,
+    ReconcileScope,
     _ReconcileWalkTracker,
     _count_cached_entries_per_root,
     _group_roots_by_device,
+    _root_display_labels,
 )
 from py.services.pending_delete_service import (
     PENDING_DELETE_DIR_NAME,
@@ -2479,10 +2481,9 @@ async def test_reconcile_walk_broadcasts_per_root_progress(tmp_path: Path, monke
 
 
 @pytest.mark.asyncio
-async def test_reconcile_prunes_entries_of_an_offline_root(tmp_path: Path):
-    """A root that is gone (drive switched off) is skipped by the walk, so its
-    cached entries are reported as missing. Locked in because it is the
-    documented consequence of refreshing with a drive powered down."""
+async def test_reconcile_keeps_entries_of_an_offline_root(tmp_path: Path):
+    """A configured root that is gone (drive switched off) must not be treated
+    as deleted: its entries are kept and reported as unreachable instead."""
     root_a = tmp_path / "a"
     root_b = tmp_path / "b"
     root_a.mkdir()
@@ -2498,9 +2499,217 @@ async def test_reconcile_prunes_entries_of_an_offline_root(tmp_path: Path):
 
     root_b.rename(tmp_path / "b_offline")
 
-    await scanner._reconcile_cache()
+    summary = await scanner._reconcile_cache()
 
     remaining = {item["file_path"] for item in scanner._cache.raw_data}
-    assert remaining == {_normalize_path(file_a)}
-    assert scanner._hash_index.get_path("hash-b0") is None
+    assert remaining == {_normalize_path(file_a), _normalize_path(file_b)}
+    assert scanner._hash_index.get_path("hash-b0") == _normalize_path(file_b)
     assert scanner._hash_index.get_path("hash-a0") == _normalize_path(file_a)
+
+    assert summary is not None
+    assert summary["removed"] == 0
+    assert summary["kept_unreachable"] == 1
+    assert summary["unavailable_paths_total"] == 1
+    assert [entry["path"] for entry in summary["unavailable_paths"]] == [
+        _normalize_path(root_b)
+    ]
+    assert summary["unavailable_paths"][0]["reason"] == "root_unreachable"
+    assert [entry["path"] for entry in summary["skipped_roots"]] == [
+        _normalize_path(root_b)
+    ]
+
+
+# --- scoped scans (issue #1108) --------------------------------------------
+
+
+@pytest.mark.asyncio
+async def test_reconcile_scoped_scan_leaves_other_roots_untouched(tmp_path: Path):
+    """Scanning one root must not add, remove or re-read anything in another."""
+    root_a = tmp_path / "a"
+    root_b = tmp_path / "b"
+    root_a.mkdir()
+    root_b.mkdir()
+    (root_a / "a0.txt").write_text("a", encoding="utf-8")
+    (root_b / "b0.txt").write_text("b", encoding="utf-8")
+
+    scanner = MultiRootDummyScanner([root_a, root_b])
+    await scanner._initialize_cache()
+
+    # Changes in B stay invisible while only A is scanned.
+    (root_b / "b0.txt").unlink()
+    (root_b / "b_new.txt").write_text("new", encoding="utf-8")
+    new_a = root_a / "a_new.txt"
+    new_a.write_text("new", encoding="utf-8")
+
+    summary = await scanner._reconcile_cache(scope=ReconcileScope(roots=(str(root_a),)))
+
+    assert summary is not None
+    assert summary["added"] == 1
+    assert summary["removed"] == 0
+    assert summary["scanned_roots"] == ["a"]
+
+    cached_paths = {item["file_path"] for item in scanner._cache.raw_data}
+    assert cached_paths == {
+        _normalize_path(root_a / "a0.txt"),
+        _normalize_path(new_a),
+        _normalize_path(root_b / "b0.txt"),
+    }
+
+
+@pytest.mark.asyncio
+async def test_reconcile_scoped_scan_removes_deleted_files_in_scope(tmp_path: Path):
+    """Deletions inside the scanned root still reconcile normally."""
+    root_a = tmp_path / "a"
+    root_b = tmp_path / "b"
+    root_a.mkdir()
+    root_b.mkdir()
+    deleted_a = root_a / "a0.txt"
+    deleted_a.write_text("a", encoding="utf-8")
+    (root_b / "b0.txt").write_text("b", encoding="utf-8")
+
+    scanner = MultiRootDummyScanner([root_a, root_b])
+    await scanner._initialize_cache()
+
+    deleted_a.unlink()
+
+    summary = await scanner._reconcile_cache(scope=ReconcileScope(roots=(str(root_a),)))
+
+    assert summary is not None
+    assert summary["removed"] == 1
+    assert scanner._hash_index.get_path("hash-a0") is None
+    assert {item["file_path"] for item in scanner._cache.raw_data} == {
+        _normalize_path(root_b / "b0.txt")
+    }
+
+
+@pytest.mark.asyncio
+async def test_reconcile_folder_scope_keeps_folder_tree_outside_scope(tmp_path: Path):
+    """A folder-scoped scan must not collapse the recorded folder list to the
+    scanned subtree (the sidebar would lose every other folder)."""
+    root = tmp_path / "loras"
+    (root / "alpha").mkdir(parents=True)
+    (root / "beta").mkdir()
+    (root / "alpha" / "m.txt").write_text("m", encoding="utf-8")
+
+    scanner = DummyScanner(root)
+    await scanner._initialize_cache()
+    folders_before = set(scanner._cache.all_folders or [])
+    assert "beta" in folders_before
+
+    (root / "alpha" / "nested").mkdir()
+    (root / "alpha" / "m.txt").unlink()
+
+    summary = await scanner._reconcile_cache(scope=ReconcileScope(folder="alpha"))
+
+    assert summary is not None
+    assert summary["removed"] == 1
+    folders_after = set(scanner._cache.all_folders or [])
+    assert "beta" in folders_after
+    assert "alpha/nested" in folders_after
+    assert {item["file_path"] for item in scanner._cache.raw_data} == set()
+
+
+@pytest.mark.asyncio
+async def test_reconcile_keeps_entries_under_unreadable_dir(tmp_path: Path, monkeypatch):
+    """A directory os.walk cannot enter (permissions, I/O error, offline
+    junction) keeps its cached entries instead of losing them."""
+    root = tmp_path / "loras"
+    sub = root / "sub"
+    sub.mkdir(parents=True)
+    (sub / "m.txt").write_text("m", encoding="utf-8")
+    (root / "top.txt").write_text("t", encoding="utf-8")
+
+    scanner = DummyScanner(root)
+    await scanner._initialize_cache()
+
+    real_scandir = os.scandir
+
+    def _failing_scandir(path=".", *args, **kwargs):
+        if os.path.normpath(str(path)) == os.path.normpath(str(sub)):
+            raise PermissionError(13, "Permission denied", str(sub))
+        return real_scandir(path, *args, **kwargs)
+
+    monkeypatch.setattr(model_scanner.os, "scandir", _failing_scandir)
+
+    summary = await scanner._reconcile_cache()
+
+    assert summary is not None
+    assert summary["removed"] == 0
+    assert summary["kept_unreachable"] == 1
+    assert summary["unavailable_paths"][0]["reason"] == "unreadable_dir"
+    assert _normalize_path(sub / "m.txt") in {
+        item["file_path"] for item in scanner._cache.raw_data
+    }
+
+
+@pytest.mark.asyncio
+async def test_reconcile_keeps_entries_under_offline_first_level_symlink(
+    tmp_path: Path, monkeypatch
+):
+    """A known first-level symlink whose target is gone protects the entries
+    that live under the link path (the linked drive is switched off)."""
+    root = tmp_path / "loras"
+    linked = root / "linked"
+    linked.mkdir(parents=True)
+    (linked / "m.txt").write_text("m", encoding="utf-8")
+
+    scanner = DummyScanner(root)
+    await scanner._initialize_cache()
+
+    # The linked folder goes away with its drive; config still knows the link.
+    linked.rename(tmp_path / "linked_offline")
+    monkeypatch.setattr(
+        model_scanner.config,
+        "iter_path_mappings",
+        lambda: [(str(tmp_path / "gone_target"), str(linked))],
+    )
+
+    summary = await scanner._reconcile_cache()
+
+    assert summary is not None
+    assert summary["removed"] == 0
+    assert summary["kept_unreachable"] == 1
+    assert summary["unavailable_paths"][0]["reason"] == "symlink_target_offline"
+    assert _normalize_path(linked / "m.txt") in {
+        item["file_path"] for item in scanner._cache.raw_data
+    }
+
+
+def test_root_display_labels_dedupe_by_parent_segments(monkeypatch):
+    labels = _root_display_labels(["/mnt/usb/loras", "/mnt/ssd/loras"])
+    assert labels == {"/mnt/usb/loras": "usb/loras", "/mnt/ssd/loras": "ssd/loras"}
+
+    # Still colliding after one parent segment: keep growing leftwards.
+    labels = _root_display_labels(["/mnt/a/models/loras", "/mnt/b/models/loras"])
+    assert labels == {
+        "/mnt/a/models/loras": "a/models/loras",
+        "/mnt/b/models/loras": "b/models/loras",
+    }
+
+    # A single root keeps the short form.
+    assert _root_display_labels(["/mnt/usb/loras"]) == {"/mnt/usb/loras": "loras"}
+
+    # Windows drive prefixes disambiguate on their own.
+    def _fake_splitdrive(path):
+        for drive in ("G:", "H:"):
+            if path.startswith(drive):
+                return drive, path[len(drive):]
+        return "", path
+
+    monkeypatch.setattr(model_scanner.os.path, "splitdrive", _fake_splitdrive)
+    labels = _root_display_labels(["G:\\x\\loras", "H:\\y\\loras"])
+    assert labels == {"G:\\x\\loras": "G: loras", "H:\\y\\loras": "H: loras"}
+
+    # Identical renderings (trailing separator / duplicated config entry) grow to
+    # the full path and then fall back to a deterministic suffix instead of
+    # silently sharing a label.
+    labels = _root_display_labels(["/mnt/x/loras", "/mnt/x/loras/"])
+    assert labels == {
+        "/mnt/x/loras": "mnt/x/loras (1)",
+        "/mnt/x/loras/": "mnt/x/loras (2)",
+    }
+
+    long_root = "/mnt/" + "d" * 60 + "/loras"
+    label = _root_display_labels([long_root])[long_root]
+    assert len(label) <= 40
+    assert label.endswith("loras")