I believe I have the same issue, I have package cups 1.6.2-1ubuntu5. When I try and do any admin task via the web interface, I get:
E [15/Sep/2013:18:51:03 +0800] [Client 11] Unknown MD5 username "rob" In my cupsd.conf file, I have the following (relevant bits only): DefaultAuthType BasicDigest (this machine is visible on a domestic LAN only) Require user @lpadmin (in various locations that previously had "require user @SYSTEM") I've tried the workarounds mentioned above, but these have not fixed the problem for me. In /var/log/kern.log, I'm seeing lots of the following: Sep 15 18:50:25 robs-computer kernel: [ 3865.265435] type=1400 audit(1379242225.411:40): apparmor="STATUS" operation="profile_replace" name="/usr/lib/cups/backend/cups-pdf" pid=18814 comm="apparmor_parser" Sep 15 18:50:25 robs-computer kernel: [ 3865.265732] type=1400 audit(1379242225.411:41): apparmor="STATUS" operation="profile_replace" name="/usr/sbin/cupsd" pid=18814 comm="apparmor_parser" -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1157318 Title: Login error in CUPS when adding a printer (or other admin procedure) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cups/+bug/1157318/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
