Might be related to : https://bugs.launchpad.net/ubuntu/+source/gdm/+bug/81670
If the problem appear again, logout/login and report if it works or not after that step. -- In Power Manager: Either HaL or Dbus is not working https://launchpad.net/bugs/85939 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs