Hello, I´ve just read Katrin Fischer´s hint in the digest and it matches my solution found an hour before: LDAP has failed to transfer into the parameter "cardnumber" out of the LDAP attribute employeeNumber because it was not set (empty) for this person in our LDAP. If the mandatory field cardnumber is empty, Koha reacts sometimes (I´ve had some other users without this problem) weird if one tries to search him/her. The trick to access the existing users without cardnumber was to create a patron report and access the bad users directly with the provided links in the report and then define a cardnumber within. I´ve changed the LDAP attribute uid (which is also persistant for us) for use as the cardnumber in Koha´s configuration file now and it worked well. The best of it: I´ve learned a lot about Koha during the debugging session. Thanks Andreas Tomiak