From a199744e2456fde1863dba0d89320ac659d04e32 Mon Sep 17 00:00:00 2001
From: neuronull <9162534+neuronull@users.noreply.github.com>
Date: Fri, 9 Jan 2026 12:56:36 -0800
Subject: [PATCH] Inform user if Desktop client already running (#17846)

---
 apps/desktop/src/main/window.main.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/apps/desktop/src/main/window.main.ts b/apps/desktop/src/main/window.main.ts
index bbdd2ad0a0f..b2008d57bcd 100644
--- a/apps/desktop/src/main/window.main.ts
+++ b/apps/desktop/src/main/window.main.ts
@@ -4,7 +4,7 @@ import { once } from "node:events";
 import * as path from "path";
 import * as url from "url";
 
-import { app, BrowserWindow, ipcMain, nativeTheme, screen, session } from "electron";
+import { app, BrowserWindow, dialog, ipcMain, nativeTheme, screen, session } from "electron";
 import { concatMap, firstValueFrom, pairwise } from "rxjs";
 
 import { LogService } from "@bitwarden/common/platform/abstractions/log.service";
@@ -122,6 +122,7 @@ export class WindowMain {
         if (!isMacAppStore()) {
           const gotTheLock = app.requestSingleInstanceLock();
           if (!gotTheLock) {
+            dialog.showErrorBox("Error", "An instance of Bitwarden Desktop is already running.");
             app.quit();
             return;
           } else {