Do they appear after you run apt-get update? It looks to me like there is not call in apt-check to update the cache.
** Changed in: update-notifier (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1224999 Title: apt-check fails to see security updates in some circumstances To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/update-notifier/+bug/1224999/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs