Mon Mar 29 07:40:52 UTC 2021

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-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to ubuntu-release-upgrader in
Ubuntu.
https://bugs.launchpad.net/bugs/1921673

Title:
  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'. Comment: I don't know what this means.

Status in ubuntu-release-upgrader package in Ubuntu:
  New

Bug description:
  I just thought it would upgrade from 18.04.5 LTS to 20 automatically
  but I get an error message and don't know what to do . What is PPA,
  PPA-Purge package and launchpad PPA? How do I know what is official
  and what is unoffical Ubuntu software?

  ProblemType: Bug
  DistroRelease: Ubuntu 18.04
  Package: ubuntu-release-upgrader-core 1:18.04.42
  ProcVersionSignature: Ubuntu 4.15.0-139.143-generic 4.15.18
  Uname: Linux 4.15.0-139-generic x86_64
  ApportVersion: 2.20.9-0ubuntu7.23
  Architecture: amd64
  CrashDB: ubuntu
  CurrentDesktop: ubuntu:GNOME
  Date: Mon Mar 29 15:13:23 2021
  InstallationDate: Installed on 2017-04-11 (1447 days ago)
  InstallationMedia: Ubuntu 16.04.2 LTS "Xenial Xerus" - Release amd64 (20170215.2)
  PackageArchitecture: all
  SourcePackage: ubuntu-release-upgrader
  UpgradeStatus: Upgraded to bionic on 2021-03-29 (0 days ago)
  VarLogDistupgradeTermlog:

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