This just happened to me (again - there's another bug about it somewhere), it was because I was using an unofficial mirror that got removed as a third-party source, and then there was no source to pull regular Ubuntu software from left.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1310089 Title: 'ubuntu-minimal' could not be located To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1310089/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs