First, make sure it isn't already running

Only one copy of Mailspring can run at a time. If a previous instance is stuck in the background, a new launch exits silently or the database error below appears. Check the system tray / menu bar for the Mailspring icon and quit from there, or end the Mailspring and mailsync processes in Task Manager / Activity Monitor, then start it again.

"We encountered a problem with your local email database"

Mailspring's cache is a SQLite database in its data folder. If it can't be opened, you're offered Quit or Rebuild. Rebuild deletes the cache and downloads your mail again; your accounts and settings are kept and nothing on the server is touched. If the dialog keeps returning:

1. Confirm no other copy of Mailspring is running (above).
2. On Windows, exclude Mailspring's data folder (%AppData%\Mailspring) from real-time antivirus scanning, which can lock the database while it's being written.
3. Install the latest version from getmailspring.com/download over the top of the existing one. A handful of past releases shipped with a broken database module for one platform, and a clean install of the current build fixes it.
4. As a last resort, quit Mailspring and use Preferences > General > Reset Accounts and Settings, or delete the data folder by hand (see Clearing the Mailspring cache).

The window is blank, white, blurry, or has colour artifacts

These are almost always graphics-driver problems. Try launching Mailspring with GPU acceleration turned off:

• Windows: right-click your Mailspring shortcut, open Properties, and add --disable-gpu to the end of the Target field. (Mailspring does this automatically after it detects a crash on startup; to re-enable acceleration later, delete the file named disable-hardware-acceleration from %AppData%\Mailspring.)
• Linux: run mailspring --disable-gpu, and make the change permanent by adding the flag to the Exec= line of the launcher.
• If the interface is blurry or the wrong size on a high-DPI display, try --force-device-scale-factor=1 as well, or adjust Scaling in Preferences > Appearance.

The tray icon appears but no window (Linux)

On Wayland desktops, older versions couldn't raise their window on first launch. Update to Mailspring 1.17.4 or later. If it still happens, launch with --ozone-platform=x11.

It broke right after an update

Download the current release from getmailspring.com/download and reinstall; on Linux the app never installs updates by itself, it only points you to the download. Every past release is available under Releases on GitHub if you need to step back a version temporarily — but please report the problem on the community forum so it gets fixed.