How do I fix "unresolvable problem occured while calculating the upgrade" (from Ubuntu 18.04 to 20.04)

It occurred while upgrading from Lubuntu 18.04.05 LTS to Lubuntu 20.04 LTS

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'.

I have only installed Steam, Pycharm Community, Python 3.8, Google Chrome, and Zoom on this PC.

My specs: Intel(R) Pentium(R) Dual CPU E2180 @ 2.00GHz 1 physical processor; 2 threads; 2 cores Intel Family G33/G31 graphics RAM: 2028964KiB (2GB) Ubuntu Distro Flavor: Lubuntu Ubuntu Version: 18.04.05 LTS

I am a newb to Ubuntu. So please help me with a simple solution. I have been waiting for this update for so long. ( I don't know how to use ppa-purge and what it is )

1 Answer

ppa-purge is a package that you can install,

sudo apt install ppa-purge 

then, read the documentation (man ppa-purge) to see (if) it can help you.