Photoshop 2022 does not start anymore

Photoshop does not start anymore after upgrade to Photoshop 2022. I am using Windows10 Prof. I uninstalled with and without removing all files, and installed again 3 times without success. At start it shows flash screen going through various steps, but simply closes flash screen without starting the app after step "Intitializing menus....". I assumed it might be available disk space, but there are 70GB availabe... Please advise.