Now that I found the correct forum, i got exactly the same issue - and a potential solution for it.
https://esoui.com/forums/newreply.ph...wreply&p=49810
"I ran into a little problem.
In Germany we use very often ö, ä and ü in usernames, so the user-path of windows contains these characters, too.
Your application does not support these characters. "Jürgen" is modified to "JÄ%rgen" and the application is unable to start.
Can you please add UTF-8 support to your application to fix this issue?"
Same goes for french and other languages, there is no UTF-8 support - so the user-folder is not to be found by minion if the name of the folder contains any special characters.