Hey there,
If the application is opening with a blank screen and forgetting the password, it may be due to bad data, permissions, or an interfering program. If you find the above info doesn’t help, we would want to see if nuking the Battle.net Application helps. The steps that follow are more thorough than a basic uninstall and covers every location that temporary files may be stored to ensure a fresh install is done for the app.
- Uninstall the application
- Press Windows key + R and type in %temp%
- Delete anything related to Blizzard or Battle.net
- Do the same for %programdata%, %localappdata%, %appdata%
- Reinstall the application. A fresh installer should be downloaded for this
If that doesn’t help, then we’d want to see if creating and switching to a new Administrator Account helps. This sets many settings to defaults and also helps with permission problems, so can be useful to do even if you’re using an admin account already.