After installing and quickly uninstalling some software on my Ubuntu machine I saw an error on each boot saying: linux the list of sources could not be read.
It also included the name that was causing the problem abc.list. In my case it was a file called waydroid.list that was causing the trouble after I had tried installing their software but realizing I didn’t want it.
To see the problem that’s happening you can open a command prompt and type:
sudo apt-get check
This should show some details of the problem.
To debug:
in Ubuntu open a command prompt and write:
ls /etc/apt/sources.list.d/
Now you should see a list returned including the offending .list file. In my case if was waydroid.list
To remove this list you’ll need to type its path. In my case the removal statement was like this:
sudo rm -r /etc/apt/sources.list.d/waydroid.list
Once this is complete you can check that the problem file was removed using this:
ls /etc/apt/sources.list.d/
After this once you reboot, the problem should be gone. At least that was my experience and it worked very well.
Justin Cooney 