Looking into other threads, I look into the log files to find obsolete packages and found these two:
2018-12-06 10:54:22,048 DEBUG Obsolete: docker-ce libsystemd-daemon0 Uninstalled them and all is working now, running the upgrade. ** Changed in: ubuntu-release-upgrader (Ubuntu) Assignee: (unassigned) => Ricardo Adao (ricadao) ** Changed in: ubuntu-release-upgrader (Ubuntu) Status: New => Fix Released -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1807131 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/1807131/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs