Public bug reported:
An unresolvable problem occurred while calculating the upgrade. This can be caused by: * Upgrading to a pre-release version of Ubuntu * Running the current pre-release version of Ubuntu * Unofficial software packages not provided by Ubuntu If none of this applies, then please report this bug using the command 'ubuntu-bug ubuntu-release-upgrader-core' in a terminal. Restoring original system state Aborting Reading package lists... Done Building dependency tree Reading state information... Done ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: ubuntu-release-upgrader-core 1:16.04.12 ProcVersionSignature: hostname 4.4.0-135.161-generic 4.4.140 Uname: Linux 4.4.0-135-generic x86_64 ApportVersion: 2.20.1-0ubuntu2 Architecture: amd64 CrashDB: ubuntu CurrentDesktop: Unity Date: Mon Sep 10 19:02:50 2018 PackageArchitecture: all SourcePackage: ubuntu-release-upgrader UpgradeStatus: Upgraded to xenial on 2018-09-10 (0 days ago) mtime.conffile..etc.update-manager.release-upgrades: 2018-09-10T17:31:46.460369 ** Affects: ubuntu-release-upgrader (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug dist-upgrade third-party-packages xenial -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1791846 Title: Can't upgrade to 18.04 from 16.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1791846/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs