diff --git a/frontend/src/components/FileExplorer.tsx b/frontend/src/components/FileExplorer.tsx
index 8a36975..8dfa35d 100644
--- a/frontend/src/components/FileExplorer.tsx
+++ b/frontend/src/components/FileExplorer.tsx
@@ -647,14 +647,18 @@ export default function FileExplorer({ onLogout }: FileExplorerProps) {
 
   async function executeDeleteSingle(file: FileItem) {
     const isPermanent = activeSection === 'trash';
-    await api.deleteFile(file.path, isPermanent);
-    if (isPermanent) {
-      loadTrash();
-    } else {
-      loadFiles(undefined, true);
+    try {
+      await api.deleteFile(file.path, isPermanent);
+      if (isPermanent) {
+        loadTrash();
+      } else {
+        loadFiles(undefined, true);
+      }
+      setDeleteConfirm(null);
+      showToast(isPermanent ? `Permanently deleted ${file.name}` : `Deleted ${file.name}`);
+    } catch (err: any) {
+      showToast(`Delete failed: ${err.message}`);
     }
-    setDeleteConfirm(null);
-    showToast(isPermanent ? `Permanently deleted ${file.name}` : `Deleted ${file.name}`);
   }
 
   async function handlePin(file: FileItem) {
diff --git a/frontend/src/lib/api.ts b/frontend/src/lib/api.ts
index 962c093..300dea6 100644
--- a/frontend/src/lib/api.ts
+++ b/frontend/src/lib/api.ts
@@ -80,6 +80,14 @@ class ApiClient {
       }
     }
 
+    if (!response.ok && endpoint !== '/api/auth/refresh') {
+      let errorMsg = `HTTP ${response.status}`;
+      try {
+        const errData = await response.clone().json();
+        if (errData.error) errorMsg = errData.error;
+      } catch {}
+      throw new Error(errorMsg);
+    }
     return response;
   }
 
@@ -202,7 +210,7 @@ class ApiClient {
   }
 
   async deleteFile(path: string, permanent: boolean = false) {
-    const query = permanent ? '?permanent=true' : '';
+    const query = permanent ? `?permanent=true&path=${encodeURIComponent(path)}` : `?path=${encodeURIComponent(path)}`;
     const res = await this.request(`/api/files/${encodeURIComponent(path)}${query}`, {
       method: 'DELETE',
     });
@@ -278,6 +286,7 @@ class ApiClient {
   // --- Pinned ---
   async listPinned() {
     const res = await this.request('/api/files/pinned');
+    if (!res.ok) throw await res.json();
     return res.json();
   }
 
@@ -286,16 +295,19 @@ class ApiClient {
       method: 'POST',
       body: { path },
     });
+    if (!res.ok) throw await res.json();
     return res.json();
   }
 
   async getTasks() {
     const res = await this.request('/api/tasks');
+    if (!res.ok) throw await res.json();
     return res.json();
   }
 
   async getSettings() {
     const res = await this.request('/api/settings');
+    if (!res.ok) throw await res.json();
     return res.json();
   }