Ok, after recreating the original folder I was able to delete the quick access folder. Still some kind of bug, but at least solved! Thanks for helping!!!

It is really the same... Items that exist, I can unpin. The 2 that are deleted, not anymore.
Screenshot would reveal nothing more...

the same menu...

62397

No... :) That is not an option in the right click menu. You can easaly test it. Make a shortcut in the quick access, after that, delete the original folder...

I added a folder to quick access in explorer. But after I deleted that folder I am unable to delete the item in quick access? :sarc: