Your description matches a known issue from the past. Please take a look at https://answers.launchpad.net/ubuntu/+question/16914 and let us know if that solution works for you.
-- [intrepid] NetworkManager: ... libhal shutdown failed https://bugs.launchpad.net/bugs/278749 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
