I think there are two issues: One is the actual bug, the other is the useless/wrong error message. You get the same error message whenever anything goes wrong, see e.g. bug #657198
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/685729 Title: Natty Computer Janitor incorrectly detects package manager -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs