When I use "sudo apt update" this error message is coming!

since i installed stacer in my ubuntu os 20.04, whenever i use update command in terminal, at the end this message appears. Can it me remove or can it cause any problem further?

Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/oguzhaninan/stacer/ubuntu focal Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

You need to temporarily disable the PPA repository and rund the command again. That PPA is having a problem right now. Go to software & updates and uncheck the PPA.

'http://ppa.launchpad.net/oguzhaninan/stacer/ubuntu focal Releas

The error suggests that the PPA you added for Stacer is not available for Focal (20.04).

You should remove the PPA:

Stacer is available from Ubuntu repository itself. Just install it from there. No need of a PPA.


One of the problems I see in getting a program from the official repository in Debian, and I seem to recall seeing it in Ubuntu back when I was running that distro, is that the version in the repositories is often not the latest version, often by several versions. (I’ve heard the same thing is common on most distros). If program X has a new release after a certain point in a distro’s release cycle there is often a lag between the new release and the distro updating the repository… (Debian usually doesn’t update the repository after testing goes into ‘feature freeze’, except for security issues) This is because the need to for someone to make the distro appropriate package, and that the new version hasn’t been as fully tested for compatibility / dependencies, etc. against the rest of the distro…

So if you want to run the latest (and greatest?) version, you need to install it from a PPA or whatever other process the developers have for your distro…

Unfortunately, there are issues w/ keeping PPA’s current (So I’ve heard, I don’t know the details) so this is also a pain… So devs will often come up with their own methods of dealing w/ updates that are specific to each program…

I would try to contact the maintainers for the program (stacer in this case) or look on their website for instructions on how to install the latest version on your distro…


Stacer has an appimage that works well. You can down load it from here
Once you download the appimage go to the downloaded app and right click and select properties and select allow to run as program.
That all there is too it. works fine on all the distros I’ve tried it on. Good luck.