Trumpfass WorkingHours version: No idea since it closes immediatly.
You can check the app version in the Windows settings.
Trumpfass OS + version: Windows 10 current version, always up to date.
Please let me know the version number
Trumpfass Do you have any idea how I can fix the app without losing the DB?
Please make a copy/backup of the database here and reinstall the app:
%localappdata%\Packages\49297T.Partl.ClockOut_jr9bq2af9farr\LocalState
Then check if the app opens. If so, try to move the backup database back to its location and restart the app.
Please let me know if that works or what exactly happens.