Your /etc/apt/sources.list file contains entries for xenial but then there are security entries for artful e.g.:
45 deb http://security.ubuntu.com/ubuntu artful-security main restricted 46 deb-src http://security.ubuntu.com/ubuntu artful-security main restricted 47 deb http://security.ubuntu.com/ubuntu artful-security universe 48 deb-src http://security.ubuntu.com/ubuntu artful-security universe 49 deb http://security.ubuntu.com/ubuntu artful-security multiverse 50 deb-src http://security.ubuntu.com/ubuntu xenial-security multiverse I'm guessing there are also packages installed from install from artful- security which are causing the release upgrader to fail. ** Changed in: ubuntu-release-upgrader (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/1778308 Title: do-release-upgrade fails To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1778308/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
