Thanks for your report. Xorg packages from the padoka PPA are blocking the upgrade. Please revert to version from the official Ubuntu repositories and try the upgrade again.
I'm closing this report because it is not an issue with Ubuntu but do not hesitate to report any issue you may find. ** 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/1786900 Title: Upgrade from 16.04 to 18.04 failed... To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1786900/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs