All AddOn settings reset after Windows Update
 

I updated my Windows 10 and afterwards I had an issue where I was logged out of every website and App on my PC and the BattleNet Launcher could not find my WoW installation anymore. I pointed it to the right folder but now all my AddOn settings are gone.

The WTF folder is still there, but it makes no difference to the game whether I leave it in the WoW folder or cut it out. If I use an old backup WTF it loads the settings without issue, but as soon as I try to copy folders from the current one to the backup it stops loading any settings.

I suppose the files or a file is somehow corrupted. Is there any way to fix this? I'm not afraid to do some coding, if it is required. I just don't know what it could be.