Public bug reported: Ran into an error while trying to upgrade from Ubuntu 16.04 to 18.04:
"Could not calculate the upgrade An unresolvable problem occurred while calculating the upgrade. This was likely caused by: * Unofficial software packages not provided by Ubuntu Please use the tool 'ppa-purge' from the ppa-purge package to remove software from a Launchpad PPA and try the upgrade again." ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: ubuntu-release-upgrader-core 1:16.04.27 ProcVersionSignature: Ubuntu 4.4.0-168.197-generic 4.4.197 Uname: Linux 4.4.0-168-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.21 Architecture: amd64 CrashDB: ubuntu CurrentDesktop: Unity Date: Wed Nov 13 16:27:13 2019 InstallationDate: Installed on 2016-06-13 (1248 days ago) InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805) PackageArchitecture: all SourcePackage: ubuntu-release-upgrader UpgradeStatus: Upgraded to xenial on 2019-11-13 (0 days ago) VarLogDistupgradeTermlog: ** 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/1852451 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/1852451/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs