Hi We are working with Debian GNU/Linux 10, MariaDB 10.3.27 and Koha 20.11.00 (using Shibboleth authentication). To avoid auto increment issues we have implemented the solution described in https://wiki.koha-community.org/wiki/DBMS_auto_increment_fix#Single_instance... - of course replacing "koha_kohadev" with the name of our own database, then restarted MariaDB. We did this even if the page says only versions prior to MariaDB 10.2.24 are affected. However, if we implement the fix or not, the following problem occurs: When we manually create a new Koha user (e. g. 84) and then try to delete it in the staff client, the message appears "An Error Occurred / 500 Internal Server Error". In Koha menu "About Koha > System information" it says "The following ids exist in both tables borrowers and deletedborrowers: 84". So we delete that number in MariaDB using SQL statement "DELETE FROM deletedborrowers where borrowernumber=84;". After that table "deletedborrowers" is empty and Koha menu "About Koha > System information" says "No warnings.". Again we try to delete the user, the internal server error occurs, etc ad infinitum. Are we doing something wrong? Best wishes: Michael -- Geschäftsführer · Diplombibliothekar BBS, Informatiker eidg. Fachausweis Admin Kuhn GmbH · Pappelstrasse 20 · 4123 Allschwil · Schweiz T 0041 (0)61 261 55 61 · E mik@adminkuhn.ch · W www.adminkuhn.ch