MtMB

I forgot about Safe Mode, and it worked. I don't have any other such software (I started guessing it's a virus since it happened all of sudden, but Avast scan haven't got anything on it).

nothing changed (app logs and separate install log) Temp.zip

apologies, last logs are from last portable, but errors are same (for some reason, installed version and install exe don't create logs now, and I said that program is updated, on home site last update listed as Jan 14th + even more outdated version works fine) I guess? they are pretty old

Hello. Yesterday my copy of Paint.NET started crashing w/o even launching (and it doesn't always show error message, just nothing happening), the days before everything was fine (program was updated around January 15th). I immediately reinstalled .NET Framework but nothing changed, system's uninstall and reinstall from fresh download don't work too, I downloaded portable version to check - same problem, tried to delete it w/ Revo Uninstaller - same error (deleted only registry stuff). Luckily I found portable 3.5.11 version on my hard drive and - it works. Pinning logs listed in error message. Temp.zip