Mattermost Desktop White Screen with Spinner on Relaunch

Applies to: Mattermost Desktop v5.13 through v6.1.x on Windows. Server side: any 10.11 - 11.5.x release.

Symptoms: The desktop app briefly shows the login screen, then displays a blank white window with a spinning circle on the second and subsequent launches.

🛑 Problem

The Mattermost Desktop app's local cache under %APPDATA%\Mattermost\ can be left in a bad state when the app is closed. The first launch after the cache is wiped works correctly, but on the next launch the app reads the bad cache, fails to finish loading, and the user is left looking at a blank window with a spinner.

This is tracked upstream as MM-67761 (Closed, fix in Desktop v6.2 - May 2026) and mattermost/desktop#3712.

Symptoms

Users or administrators experiencing this issue will see:

• Login screen renders for a fraction of a second, then is replaced by a blank white window with a spinner.
• Webapp via browser is unaffected against the same server.
• Ctrl+Shift+R (hard reload) restores the app for one launch only; closing and reopening reproduces the white screen.
• Removing %APPDATA%\Mattermost\Cache restores the app for one launch; removing %APPDATA%\Mattermost\Code Cache restores it for several launches.

✅ Solution

Upgrade to Mattermost Desktop v6.2

Upgrade affected clients to Mattermost Desktop v6.2 or later. This version contains the permanent fix for the cache corruption that causes the blank window.

Additional Resources

For more information, see:

MM-67761 - Server stuck on loading screen

GitHub mattermost/desktop#3712 - Stuck on Blue Loading Screen