I am experiencing the same effect and have added a screen shot at bug 998125
I performed some further investigation and it seems to me thet the error appears especially when you click on the tick mark besides a header line ("Important security updates", "Recommended updates", etc.). Right clicking on a tickmark and choosing select all or deselect all usually did not trigger the error. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/939705 Title: update-manager doesn't correctly solve dependencies when unselecting package To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/update-manager/+bug/939705/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs