Can't export animated gif in photoshop

Hello, 

I also asked the help desk, but they can't help me. For the emailingprogram i use i wanted to upload a gif because mp4 doesnt work there. I always made an animated gif in photoshop and saved it for web. Now with the version 22.3.1 i couldnt export my psd file to an gif and with the latest version 22.4 it also doesn't work. When i click save or export i get the following popup: this action cannot be accomplished because of an unknown error.

I tried a lot of things, i normally work on a shared server. I tried it local, i exported al my layers into jpegs and made a new document with timeline. I did a video timeline and tried withe a frame timeline... don't know what else i can try...  but i get the same popup over and over again. 

I hope anyone can help me, because it's really frustrating. 

Asking for help as a desperate 'newbie'.