@Davidlee,

Yeah, once a Kubuntu release hits EOL, the upgrade servers get shut off, which is why you’re seeing that “release not available” message. The updater can’t find the next release to hop to.

You’ve basically got two workable paths:

1. Point your sources to old-releases so the upgrader can function again, which lets you upgrade in place without wiping your settings.
2. Use a backup + reinstall (Which you’re trying to avoid, fair enough).

If you want to go the in-place upgrade route (the less painful one):

sudo sed -i 's/archive.ubuntu.com/old-releases.ubuntu.com/g' /etc/apt/sources.list
sudo apt update && sudo apt full-upgrade
sudo do-release-upgrade

This usually lets you jump to the next release that still has upgrade metadata, and from there you can hop to the LTS.

No guarantees (KDE flavors can be moody), but it does save your settings and PPAs in most cases.

If you want to go the in-place upgrade route (the less painful one):

Can someone please tell me how to upgrade an EOL, unsupported Kubuntu release to the next available LTS release? Every attempt to upgrade my Kubuntu 24.10 install just gives me ‘release not available‘.

I know a fresh install would work, but that means losing all my user settings and PPA-installed apps. KDE + Ubuntu can be a real pain to maintain.

Neon on the other hand is very simple and streamlined, lightweight in programs, etc. Both run very well on older systems and look and feel solid. I thought I would try Linux and keep Windows around but am now noticing I’ve not gone back to Windows in months.

It takes a bit of time to get your preferences sorted out and that’s part of the fun of learning something new. KDE is the version I like best. I’ve looked at many many distros. I have tons of usb drives with multi-live session OS and I’ve stopped looking.

“Nothing beats tumbleweed”

Maybe in your opinion but, for me, PCLinuxOS run circles around both Tumbleweed and MX.

BEST is a very vague and subjective definition that’s based on personal preference. Just because something is BEST for you does not mean that it is BEST for anyone else. We all have our own set of requirements and criteria by which we judge distros and declare it “The Best”.