Comment 19 worked for me after reboot on 14.04. The error happened in relation to manual a password reset I did (replaced shadow and passwd with a backup).
https://bugs.launchpad.net/ubuntu/+source/policykit-desktop-privileges/+bug/1240336/comments/19
Comment 19 worked for me after reboot on 14.04. The error happened in relation to manual a password reset I did (replaced shadow and passwd with a backup).
https:/ /bugs.launchpad .net/ubuntu/ +source/ policykit- desktop- privileges/ +bug/1240336/ comments/ 19