diff --git a/electron/main.cjs b/electron/main.cjs
index 94a33678..e9d3c434 100644
--- a/electron/main.cjs
+++ b/electron/main.cjs
@@ -1654,7 +1654,7 @@ ipcMain.handle("clear-remote-sync-config", async () => {
   return result;
 });
 
-ipcMain.handle("save-remote-sync-jwt", (_event, token) => {
+ipcMain.handle("save-remote-sync-jwt", async (_event, token) => {
   const result = remoteSync.saveRemoteSyncJwt(token);
   if (result.success) {
     remoteSync.getRemoteSyncEngine()?.updateStatus({
@@ -1662,7 +1662,8 @@ ipcMain.handle("save-remote-sync-jwt", (_event, token) => {
       needsReauth: false,
       lastError: null,
     });
-    remoteSync.getRemoteSyncEngine()?.syncNow();
+    const status = await remoteSync.getRemoteSyncEngine()?.syncNow();
+    return { ...result, status: status || null };
   }
   return result;
 });
diff --git a/src/ui/AppShell.tsx b/src/ui/AppShell.tsx
index 38e8fe1d..e3de72d4 100644
--- a/src/ui/AppShell.tsx
+++ b/src/ui/AppShell.tsx
@@ -333,6 +333,8 @@ export function AppShell({
   const [remoteSyncInitialServerUrl, setRemoteSyncInitialServerUrl] = useState<
     string | undefined
   >(undefined);
+  const [remoteSyncReconnectRequested, setRemoteSyncReconnectRequested] =
+    useState(false);
   const [sidebarWidth, setSidebarWidth] = useState(() => {
     const saved = localStorage.getItem("termix_sidebarWidth");
     return saved ? parseInt(saved, 10) : 291;
@@ -2714,6 +2716,10 @@ export function AppShell({
                 setUserPrefs((current) => ({ ...current, ...updates }))
               }
               remoteSyncInitialServerUrl={remoteSyncInitialServerUrl}
+              remoteSyncReconnectRequested={remoteSyncReconnectRequested}
+              onRemoteSyncReconnectHandled={() =>
+                setRemoteSyncReconnectRequested(false)
+              }
             />
           </div>
         )}
@@ -2854,6 +2860,7 @@ export function AppShell({
               onReconnect={() => {
                 setRailView("user-profile");
                 if (!sidebarOpen) setSidebarOpen(true);
+                setRemoteSyncReconnectRequested(true);
               }}
             />
             <MigrationNoticeDialog
diff --git a/src/ui/auth/ElectronLoginForm.tsx b/src/ui/auth/ElectronLoginForm.tsx
index 1a799b2c..77c954ac 100644
--- a/src/ui/auth/ElectronLoginForm.tsx
+++ b/src/ui/auth/ElectronLoginForm.tsx
@@ -20,6 +20,10 @@ interface SaveRemoteSyncJwtResult {
   success: boolean;
   reason?: string;
   error?: string;
+  status?: {
+    needsReauth?: boolean;
+    lastError?: string | null;
+  } | null;
 }
 
 const AUTH_MESSAGE_SOURCES = new Set([
@@ -56,27 +60,33 @@ export function ElectronLoginForm({
       setIsAuthenticating(true);
 
       try {
-        if (token) {
-          if (targetPurpose === "remoteSync") {
-            // The main process refuses to persist the JWT when it has no OS
-            // keyring to encrypt it with, and reports that by resolving with
-            // success: false. Dropping the result signs the user in against a
-            // store that kept nothing, so the next sync tick calls a session
-            // that was never saved expired.
-            const result = (await window.electronAPI?.invoke?.(
-              "save-remote-sync-jwt",
-              token,
-            )) as SaveRemoteSyncJwtResult | undefined;
-            if (!result?.success) {
-              throw new Error(
-                result?.reason === "encryption_unavailable"
-                  ? t("errors.keyringUnavailable")
-                  : result?.error || t("errors.authTokenSaveFailed"),
-              );
-            }
-          } else {
-            localStorage.setItem("jwt", token);
+        if (targetPurpose === "remoteSync") {
+          if (!token) {
+            throw new Error(t("errors.authTokenMissing"));
           }
+          // The main process refuses to persist the JWT when it has no OS
+          // keyring to encrypt it with, and reports that by resolving with
+          // success: false. Dropping the result signs the user in against a
+          // store that kept nothing, so the next sync tick calls a session
+          // that was never saved expired.
+          const result = (await window.electronAPI?.invoke?.(
+            "save-remote-sync-jwt",
+            token,
+          )) as SaveRemoteSyncJwtResult | undefined;
+          if (!result?.success) {
+            throw new Error(
+              result?.reason === "encryption_unavailable"
+                ? t("errors.keyringUnavailable")
+                : result?.error || t("errors.authTokenSaveFailed"),
+            );
+          }
+          if (result.status?.needsReauth || result.status?.lastError) {
+            throw new Error(
+              result.status.lastError || t("errors.authTokenRejected"),
+            );
+          }
+        } else if (token) {
+          localStorage.setItem("jwt", token);
         }
         await onAuthSuccessRef.current(token);
       } catch (err) {
diff --git a/src/ui/locales/en.json b/src/ui/locales/en.json
index bf467b7d..c13b0935 100644
--- a/src/ui/locales/en.json
+++ b/src/ui/locales/en.json
@@ -500,6 +500,8 @@
     "disconnectButton": "Disconnect",
     "syncNowButton": "Sync Now",
     "syncing": "Syncing...",
+    "syncSuccess": "Remote sync completed",
+    "syncUnavailable": "Remote sync could not be started",
     "serverUrl": "Server URL",
     "enterServerUrl": "Please enter a server URL",
     "mustIncludeProtocol": "Server URL must start with http:// or https://",
@@ -2966,6 +2968,8 @@
     "resetCodeRateLimited": "Rate limited: Too many verification attempts. Please try again later.",
     "resetCodeRateLimitedWithTime": "Rate limited: Too many verification attempts. Please wait {{time}} seconds before trying again.",
     "authTokenSaveFailed": "Failed to save authentication token",
+    "authTokenMissing": "The server did not return a new authentication token. Please sign in again.",
+    "authTokenRejected": "The remote server rejected the new authentication token",
     "keyringUnavailable": "Signed in, but the session could not be stored: this system has no keyring available to encrypt it with. Start a Secret Service (such as gnome-keyring or KWallet) and sign in again.",
     "failedToLoadServer": "Failed to load server",
     "remoteServerRequired": "Remote server required. Connect a remote server in Settings to use this connection type."
diff --git a/src/ui/locales/translated/zh_CN.json b/src/ui/locales/translated/zh_CN.json
index 5fd9f6ca..6fea54fe 100644
--- a/src/ui/locales/translated/zh_CN.json
+++ b/src/ui/locales/translated/zh_CN.json
@@ -474,6 +474,8 @@
     "disconnectButton": "断开",
     "syncNowButton": "立即同步",
     "syncing": "正在同步...",
+    "syncSuccess": "远程同步已完成",
+    "syncUnavailable": "无法启动远程同步",
     "serverUrl": "服务器 URL",
     "enterServerUrl": "请输入服务器网址",
     "mustIncludeProtocol": "服务器 URL 必须以 http:// 或 https:// 开头。",
@@ -2820,6 +2822,8 @@
     "resetCodeRateLimited": "频率受限：验证尝试次数过多，请稍后再试。",
     "resetCodeRateLimitedWithTime": "频率受限：验证尝试次数过多，请等待 {{time}} 秒后再试。",
     "authTokenSaveFailed": "保存认证令牌失败",
+    "authTokenMissing": "服务器没有返回新的认证令牌，请重新登录。",
+    "authTokenRejected": "远程服务器拒绝了新的认证令牌",
     "keyringUnavailable": "已登录，但会话无法保存：此系统没有可用于加密的密钥环。请启动密钥服务（例如 gnome-keyring 或 KWallet）并重新登录。",
     "failedToLoadServer": "加载服务器失败",
     "remoteServerRequired": "需要远程服务器。请在“设置”中连接远程服务器以使用此连接类型。"
diff --git a/src/ui/settings/RemoteSyncPanel.tsx b/src/ui/settings/RemoteSyncPanel.tsx
index ce40c546..d653a278 100644
--- a/src/ui/settings/RemoteSyncPanel.tsx
+++ b/src/ui/settings/RemoteSyncPanel.tsx
@@ -11,6 +11,7 @@ import {
 import { RemoteSyncServerPicker } from "./RemoteSyncServerPicker.tsx";
 import { ElectronLoginForm } from "@/auth/ElectronLoginForm.tsx";
 import { invalidateServerStatusCache } from "@/lib/hosts-request-cache.ts";
+import { toast } from "sonner";
 
 interface RemoteSyncConfig {
   serverUrl: string;
@@ -32,9 +33,15 @@ type DesktopSettings = { defaultConnectionOrigin: "local" | "remote" };
 
 interface RemoteSyncPanelProps {
   initialServerUrl?: string;
+  reconnectRequested?: boolean;
+  onReconnectRequestHandled?: () => void;
 }
 
-export function RemoteSyncPanel({ initialServerUrl }: RemoteSyncPanelProps) {
+export function RemoteSyncPanel({
+  initialServerUrl,
+  reconnectRequested = false,
+  onReconnectRequestHandled,
+}: RemoteSyncPanelProps) {
   const { t } = useTranslation();
   const [config, setConfig] = useState<RemoteSyncConfig | null>(null);
   const [status, setStatus] = useState<RemoteSyncStatus | null>(null);
@@ -79,8 +86,21 @@ export function RemoteSyncPanel({ initialServerUrl }: RemoteSyncPanelProps) {
     setStep("picker");
   }, [initialServerUrl, config]);
 
+  useEffect(() => {
+    if (!reconnectRequested || !config?.serverUrl) return;
+    setPendingServerUrl(config.serverUrl);
+    setStep("login");
+    onReconnectRequestHandled?.();
+  }, [config?.serverUrl, onReconnectRequestHandled, reconnectRequested]);
+
   const handleConnectClick = () => setStep("picker");
 
+  const handleReconnectClick = () => {
+    if (!config?.serverUrl) return;
+    setPendingServerUrl(config.serverUrl);
+    setStep("login");
+  };
+
   const handleServerConfigured = (serverUrl: string) => {
     setPendingServerUrl(serverUrl);
     setStep("login");
@@ -99,7 +119,19 @@ export function RemoteSyncPanel({ initialServerUrl }: RemoteSyncPanelProps) {
   const handleSyncNow = async () => {
     setSyncingNow(true);
     try {
-      await window.electronAPI?.invoke?.("remote-sync-now");
+      const result = (await window.electronAPI?.invoke?.("remote-sync-now")) as
+        RemoteSyncStatus | null | undefined;
+      if (!result || result.needsReauth || result.lastError) {
+        toast.error(result?.lastError || t("remoteSync.syncUnavailable"));
+      } else {
+        toast.success(t("remoteSync.syncSuccess"));
+      }
+    } catch (error) {
+      toast.error(
+        error instanceof Error && error.message
+          ? error.message
+          : t("remoteSync.syncUnavailable"),
+      );
     } finally {
       setSyncingNow(false);
       await refresh();
@@ -171,7 +203,7 @@ export function RemoteSyncPanel({ initialServerUrl }: RemoteSyncPanelProps) {
                     type="button"
                     size="sm"
                     className="text-[10px] h-7"
-                    onClick={handleConnectClick}
+                    onClick={handleReconnectClick}
                   >
                     {t("remoteSync.bannerReconnect")}
                   </Button>
diff --git a/src/ui/sidebar/UserProfilePanel.tsx b/src/ui/sidebar/UserProfilePanel.tsx
index 18560c9e..9a55f8c4 100644
--- a/src/ui/sidebar/UserProfilePanel.tsx
+++ b/src/ui/sidebar/UserProfilePanel.tsx
@@ -495,10 +495,14 @@ export function UserProfilePanel({
   userPrefs,
   onPrefsChange,
   remoteSyncInitialServerUrl,
+  remoteSyncReconnectRequested,
+  onRemoteSyncReconnectHandled,
 }: {
   username?: string;
   onLogout?: () => void;
   remoteSyncInitialServerUrl?: string;
+  remoteSyncReconnectRequested?: boolean;
+  onRemoteSyncReconnectHandled?: () => void;
   userPrefs?: {
     reopenTabsOnLogin: boolean;
     storageMode?: string | null;
@@ -1667,7 +1671,11 @@ export function UserProfilePanel({
 
           {isElectron() && (
             <div className="border-t border-border pt-3 mt-3">
-              <RemoteSyncPanel initialServerUrl={remoteSyncInitialServerUrl} />
+              <RemoteSyncPanel
+                initialServerUrl={remoteSyncInitialServerUrl}
+                reconnectRequested={remoteSyncReconnectRequested}
+                onReconnectRequestHandled={onRemoteSyncReconnectHandled}
+              />
             </div>
           )}
 
diff --git a/src/ui/tests/settings/RemoteSyncPanel.test.tsx b/src/ui/tests/settings/RemoteSyncPanel.test.tsx
new file mode 100644
index 00000000..1059c694
--- /dev/null
+++ b/src/ui/tests/settings/RemoteSyncPanel.test.tsx
@@ -0,0 +1,87 @@
+import {
+  cleanup,
+  fireEvent,
+  render,
+  screen,
+  waitFor,
+} from "@testing-library/react";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+const { toast, invoke } = vi.hoisted(() => ({
+  toast: { error: vi.fn(), success: vi.fn() },
+  invoke: vi.fn(),
+}));
+
+vi.mock("sonner", () => ({ toast }));
+vi.mock("react-i18next", () => ({
+  useTranslation: () => ({ t: (key: string) => key }),
+}));
+vi.mock("@/auth/ElectronLoginForm.tsx", () => ({
+  ElectronLoginForm: ({ serverUrl }: { serverUrl: string }) => (
+    <div data-testid="remote-login">{serverUrl}</div>
+  ),
+}));
+
+import { RemoteSyncPanel } from "../../settings/RemoteSyncPanel";
+
+const config = {
+  serverUrl: "http://192.168.3.175:6060",
+  connectedAt: "2026-08-27T00:00:00.000Z",
+};
+const status = {
+  connected: true,
+  syncing: false,
+  lastSyncedAt: null,
+  lastError: "Remote session expired",
+  needsReauth: true,
+};
+
+beforeEach(() => {
+  invoke.mockImplementation((channel: string) => {
+    if (channel === "get-remote-sync-config") return Promise.resolve(config);
+    if (channel === "get-remote-sync-status") return Promise.resolve(status);
+    if (channel === "get-desktop-settings") {
+      return Promise.resolve({ defaultConnectionOrigin: "local" });
+    }
+    if (channel === "remote-sync-now") return Promise.resolve(status);
+    return Promise.resolve(null);
+  });
+  Object.defineProperty(window, "electronAPI", {
+    configurable: true,
+    value: { invoke, onRemoteSyncStatusChanged: vi.fn() },
+  });
+});
+
+afterEach(() => {
+  cleanup();
+  vi.clearAllMocks();
+});
+
+describe("RemoteSyncPanel", () => {
+  it("opens the configured server login when the banner requests reconnect", async () => {
+    const onHandled = vi.fn();
+    render(
+      <RemoteSyncPanel
+        reconnectRequested
+        onReconnectRequestHandled={onHandled}
+      />,
+    );
+
+    expect((await screen.findByTestId("remote-login")).textContent).toBe(
+      config.serverUrl,
+    );
+    expect(onHandled).toHaveBeenCalledOnce();
+  });
+
+  it("shows the sync failure returned by the main process", async () => {
+    render(<RemoteSyncPanel />);
+    const syncButton = await screen.findByRole("button", {
+      name: /remoteSync.syncNowButton/,
+    });
+    fireEvent.click(syncButton);
+
+    await waitFor(() => {
+      expect(toast.error).toHaveBeenCalledWith("Remote session expired");
+    });
+  });
+});