Public bug reported:
I tried to remove packages skypeforlinux and zoom that were installed,
but without success.
$ sudo do-release-upgrade -d
Checking for a new Ubuntu release
Get:1 Upgrade tool signature [1 554 B]
Get:2 Upgrade tool [1 342 kB]
Fetched 1 343 kB in 0s (0 B/s)
authenticate 'focal.tar.gz' against 'focal.tar.gz.gpg'
extracting 'focal.tar.gz'
Reading cache
Checking package manager
Reading package lists... Done
Building dependency tree
Reading state information... Done
Hit http://fr.archive.ubuntu.com/ubuntu bionic InRelease
Hit http://fr.archive.ubuntu.com/ubuntu bionic-updates InRelease
Hit http://fr.archive.ubuntu.com/ubuntu bionic-backports InRelease
Ign http://dl.google.com/linux/chrome/deb stable InRelease
Hit http://dl.google.com/linux/chrome/deb stable Release
Hit https://repo.skype.com/deb stable InRelease
Get:1 http://security.ubuntu.com/ubuntu bionic-security InRelease [88,7 kB]
Fetched 88,7 kB in 0s (0 B/s)
Reading package lists... Done
Building dependency tree
Reading state information... Done
Checking for installed snaps
Calculating snap size requirements
Updating repository information
Third party sources disabled
Some third party entries in your sources.list were disabled. You can
re-enable them after the upgrade with the 'software-properties' tool
or your package manager.
To continue please press [ENTER]
Hit http://fr.archive.ubuntu.com/ubuntu focal InRelease
Hit http://fr.archive.ubuntu.com/ubuntu focal-updates InRelease
Hit http://fr.archive.ubuntu.com/ubuntu focal-backports InRelease
Get:1 http://security.ubuntu.com/ubuntu focal-security InRelease [107 kB]
Fetched 107 kB in 0s (0 B/s)
Checking package manager
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating the changes
Calculating the changes
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.
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'.
Restoring original system state
Aborting
Reading package lists... Done
Building dependency tree
Reading state information... Done
ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubuntu-release-upgrader-core 1:18.04.37
ProcVersionSignature: Ubuntu 5.3.0-51.44~18.04.2-generic 5.3.18
Uname: Linux 5.3.0-51-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.14
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Sat May 9 23:02:52 2020
InstallationDate: Installed on 2019-08-20 (263 days ago)
InstallationMedia: Ubuntu 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to bionic on 2020-05-09 (0 days ago)
** Affects: ubuntu-release-upgrader (Ubuntu)
Importance: Undecided
Status: New
