SOLVED: Support

[lokize]

I had already tried all of those steps, and none of them worked. No matter which user I created, it would always link to an existing one without admin permissions. However, I ended up trying something completely different:

I opened the database and deleted all users

I set <IsStartupWizardCompleted>false</IsStartupWizardCompleted>

I restarted the service and recreated the admin user — and it worked.

Thanks for the support, and I hope this helps others who run into the same issue!