Seems like the culprit is Apparmor : root@iutm-inf-ghost2:/var/log# tail -300 /var/log/kern.log
Mar 25 16:37:46 iutm-inf-ghost2 kernel: [ 9297.515512] type=1400 audit(1364225866.005:10922911): apparmor="DENIED" operation="capable" parent=1 profile="/usr/sbin/cupsd" pid=17770 comm="cupsd" pid=17770 comm="cupsd" capability=29 capname="audit_write" "aa-complain /etc/apparmor.d/usr.sbin.cupsd" helps, as a temporary workaround. F. NASS -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to cups in Ubuntu. https://bugs.launchpad.net/bugs/1157318 Title: Login error in CUPS when adding a printer (or other admin procedure) Status in “cups” package in Ubuntu: Confirmed Bug description: Using Raring (13.04): When you go to http://localhost:631 to do admin tasks in cups, and enter your login details, the system keep asking the user/password in a loop. In the cups log: E [19/Mar/2013:18:20:10 +0100] [Client 17] pam_authenticate() returned 4 (System error) E [19/Mar/2013:18:20:42 +0100] [Client 16] pam_authenticate() returned 4 (System error) E [19/Mar/2013:18:20:49 +0100] [Client 15] pam_authenticate() returned 4 (System error) In the auth log no info. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cups/+bug/1157318/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp