we found the reason of the error and now it is solved, we everybody can login again.
Thanks for the support.

Do you mean this link?
https://tcd-hummelo.nl/admidio/adm_program/overview.php

yes that is correct

I tried to update to new version but that was not possible as the same problem occurred, I had to login and got back that field Username was empty

Since 24-01-2025 nobody can login anymore. After filling in username and password the following message appears: The field Username is empty. We have never had any problem after installing Admidio in september 2021. Please help us, so our 890 members can login again. link to out membership site: htt...