I am trying to upgrade from 18.04 to 20.04 but I get the error message:
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 looked at the main.log and apt.log, but my Ubuntu skills are not good enough to understand them and I am unsure if I can just delete all the broken packages.
