[Bug 1899131] [NEW] 18.04 can't upgrade to 20.04

[Liu]

Public bug reported:

showed notificaiton bellow:
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'. 

and I checked the ppa is OK.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubuntu-release-upgrader-core 1:18.04.39
ProcVersionSignature: Ubuntu 5.4.0-49.53~18.04.1-generic 5.4.65
Uname: Linux 5.4.0-49-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.18
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Fri Oct  9 15:39:52 2020
InstallationDate: Installed on 2019-12-26 (287 days ago)
InstallationMedia: Ubuntu 18.04.3 LTS "Bionic Beaver" - Release amd64 (20190805)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to bionic on 2020-10-09 (0 days ago)

** Affects: ubuntu-release-upgrader (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: amd64 apport-bug bionic dist-upgrade package-from-proposed

-- 
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/1899131

Title:
  18.04 can't upgrade to 20.04

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

Bug description:
  showed notificaiton bellow:
  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'. 

  and I checked the ppa is OK.

  ProblemType: Bug
  DistroRelease: Ubuntu 18.04
  Package: ubuntu-release-upgrader-core 1:18.04.39
  ProcVersionSignature: Ubuntu 5.4.0-49.53~18.04.1-generic 5.4.65
  Uname: Linux 5.4.0-49-generic x86_64
  NonfreeKernelModules: nvidia_modeset nvidia
  ApportVersion: 2.20.9-0ubuntu7.18
  Architecture: amd64
  CrashDB: ubuntu
  CurrentDesktop: ubuntu:GNOME
  Date: Fri Oct  9 15:39:52 2020
  InstallationDate: Installed on 2019-12-26 (287 days ago)
  InstallationMedia: Ubuntu 18.04.3 LTS "Bionic Beaver" - Release amd64 (20190805)
  PackageArchitecture: all
  SourcePackage: ubuntu-release-upgrader
  UpgradeStatus: Upgraded to bionic on 2020-10-09 (0 days ago)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1899131/+subscriptions