Common causes

  • No network or the updater is blocked by security software;
  • The input method is busy — close typing windows first;
  • Insufficient permission on the install folder.

Fixes

  1. Download the latest installer from the official site and install over it (dictionary and settings are kept);
  2. Or use Repair Install under Settings → About;
  3. If it still fails, run the installer as administrator.

Rollback

Official archives host older builds you can install over the current one, though very old versions may lose cloud input.