What does this mean?

When I check for updates I get this message:

Does anyone know what this means and how to get rid of it?

Thanks for any help you can give.

This question was asked before several times:

But I think a reboot should work. In one of the cases it did.


Thanks for the link. I saw in the thread where someone else had tried searching for a solution but the search function didn't show anything. I also tried searching first before posting and didn't see a solution. I guess it was the way I worded my seach.

Anyway I tried reinstalling Gnome software as Aravisian suggested and then it said reboot which I did. That problem went away but now I am back to a problem that was there for several days before that problem showed up. Each time I checked for updates before the last problem I got this screen which stayed on for several hours until I turned off my PC.

As you can see it says installing but never does anything. I tried using Synaptic to do a reinstall but a search in Synaptic did not show KDE Application Platform so I didn't know what to try next. I did do : Sudo apt-get update but as you can see the problem is still there.

Thanks again for your help.

Did you killall gnome-software, then remove the gnome-software cache? Then reinstall or re-launch gnome-software.

You may also try

sudo apt install --reinstall ca-certificates


Thanks to both of you. EE's link helped me solve the first problem and your command solved the last problem. All clear now when I do a check for updates. I had been trying to solve this on my own for several days now and with the help from the two of you I got both problems solved in less than an hour.

Thanks again.