If you are trying to upgrade your software on the same release of Ubuntu and not perform an upgrade to a different release then you want to file a bug report about update-manager. Please use ubuntu-bug update-manager so that the proper log files will be gathered. Thanks!
** Changed in: ubuntu-release-upgrader (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1500258 Title: core upgrade failing To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1500258/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs