unable to upgrade 18.04 to 20.04.1 u" An unresolvable problem occurred while calculating the upgrade."

[Stephen Gill]

After upgrade failed due to 3rd party sources I unticked/deselected google, TeamViewer and graphics/ubuntu/bionic/main (sorry, not precise - from my notes). Then I power cycled the PC.

I'm running upgrade from limited user account and authenticating when requested.

Do I need to install from downloaded image?

Full error message follows.

Could not calculate the upgrade

An unresolvable problem occurred while calculating the upgrade.

 If none of this applies, then please report this bug using the command 'ubuntu-bug ubuntu-release-upgrader-core' in a terminal. If you want to investigate this yourself the log files in '/var/log/dist-upgrade' will contain details about the upgrade. Specifically, look at 'main.log' and 'apt.log'.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubuntu-release-upgrader-core 1:18.04.41
ProcVersionSignature: Ubuntu 4.15.0-128.131-generic 4.15.18
Uname: Linux 4.15.0-128-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.20
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Thu Dec 17 07:18:49 2020
InstallationDate: Installed on 2019-01-18 (698 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to bionic on 2020-12-16 (0 days ago)
VarLogDistupgradeTermlog:

[Brian Murray (brian-murray)]

Reviewing the files from your upgrade attempt you seem to have enabled a PPA that provides Xorg packages. This will prevent the upgrade as that PPA contains package version numbers greater than the release to which you are upgrading. You can revert the PPA by installing the ppa-purge package from the official Ubuntu archive and then running 'sudo ppa-purge ppa:oibaf/graphics-drivers'. After that you can try upgrading again and if it still fails open a new bug report. Thanks and good luck!

[Steve Gill (h4-s-61)]

Awesome!  Thanks Brian!

Your instructions are clear.  I'll have a go as soon as I have time and
will advise.

With gratitude, Steve

On 10/04/2021 7:00 AM, Brian Murray wrote:
> *** This bug is a duplicate of bug 1069133 ***
> https://bugs.launchpad.net/bugs/1069133
>
> Reviewing the files from your upgrade attempt you seem to have enabled a
> PPA that provides Xorg packages. This will prevent the upgrade as that
> PPA contains package version numbers greater than the release to which
> you are upgrading. You can revert the PPA by installing the ppa-purge
> package from the official Ubuntu archive and then running 'sudo ppa-
> purge ppa:oibaf/graphics-drivers'. After that you can try upgrading
> again and if it still fails open a new bug report. Thanks and good
> luck!
>
> ** Changed in: ubuntu-release-upgrader (Ubuntu)
> Status: New => Invalid
>
> ** Tags added: ppa xorg-oibaf-ppa
>
> ** This bug has been marked a duplicate of bug 1069133
> Get upgrade error 12.04 - 12.10 "Could not determine upgrade" - xorg from ppa
>