Can't upgrade from Kubuntu 18.04 LTS from Kubuntu 20.04 LTS

Question

I still can't upgrade from 18.04.x LTS to 20.x.x LTS. Still receiving this error:

Checking for a new Ubuntu release                                                                                                                                                                                                            
There is no development version of an LTS available.                                                                                                                                                                                         
To upgrade to the latest non-LTS develoment release                                                                                                                                                                                          
set Prompt=normal in /etc/update-manager/release-upgrades.

after running the following commands:

sudo apt-get update && sudo apt-get dist-upgrade 
sudo do-release-upgrade -m desktop

or

pkexec do-release-upgrade -m desktop -f DistUpgradeViewKDE

as mentioned here in the Ubuntu help wiki

Running the following command:

sudo do-release-upgrade -d

returned this error message:

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

I searched for solutions and asked people but until now no one was able to provide a clear answer.

I think that the bug mentioned here by the user the100rabh in the question Upgrade to Kubuntu 20.04 from Kubuntu 18.04 is still active and was not fixed.

Please let me know if there is a solution to this problem.

Thank you.

---

@kyodake: I already deleted any ppa entry in the /etc/apt/ so in theory the upgrade should work, but it doesn't.

I looked into /var/log/dist-upgrade/<date>/apt.log and noticed that apt reported broken packages or held back packages. However, when I checked in Muon Package Manager I didn't find any broken packages or anything else.

Running the following commands returned nothing:

sudo apt-get --fix-broken install
sudo apt-get clean
sudo apt-get install -f
sudo dpkg --configure -a
sudo apt-get update
sudo rm /var/lib/apt/lists/* -vf
sudo apt-get update
sudo apt-get clean
sudo apt-get autoclean
sudo apt-get autoremove
sudo dpkg --configure -a
sudo apt-get update

Any ideas?

Maybe I should back-up my data and do a clean install. However, I don't think this is a good solution every time when something is going wrong.

Thank you.

Answer 1

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.

grep -i ppa.launchpad.net /etc/apt/sources.list.d/*.list

This will give the ppa list

The path of the PPA needed to uninstall it with ppa-purge, is the text found between ppa.launchpad.net and ubuntu.

For example, to:

http://ppa.launchpad.net/jrm-smnt/ppa/ubuntu

PPA path is: jrm-smnt/ppa

So, in ppa-purge you are going to put:

sudo ppa-purge ppa:jrm-smnt/ppa

For each ppa.