Lost desktop environment on latest update (again)

[SamCaine]

I've had to boot into Windows to try to find a solution to this problem.

A couple of weeks ago this happened as per the previous thread and I followed the advice posted there and managed to get everything working again.

Now it's happened again; I received a notification that there were updates available. I opened a command line and entered the update command, there were a host of packages held back, and a massive list of packages that would be removed and a few packages to update. Like an idiot I accepted Y and the update commenced, and then my desktop died and I was dumped into a black screen with some writing at the top followed by a blinking cursor. I did Ctrl-Alt-F1 and entered the CL interface and tried the command suggested previously and nothing worked.

So, following an update I'm now left with no Desktop Environment.

Can anyone suggest a solution, firstly to get the DE back, and secondly to stop this happening a third time. Perhaps I should just not bothering to update in future?

[Schwarzer Kater]

2. Unfortunately something like this can happen for example if you use apt full-upgrade instead of apt upgrade and/or don't read if anything and what is removed…
To be really sure that this doesn't happen in the future I would suggest that you use Discover only to update your system.

1. To get your removed packages (aka "desktop environment" in your case) back, afaik you could look up what has been removed exactly in /var/log/apt/history.log and just reinstall those packages again.

[kc1di]

You can try to recover the packages that were deleted that run the desktop. That may be a long process another way you could try is install the kde-plasma-desktop package and see if it will replace the lost packages.

sudo apt install kde-plasma-desktop

When you want to update your system at least for the time being I would not use the terminal but the Discover update tool to avoid this problem in the future.
Good luck.

[claydoh]

You can try to recover the packages that were deleted that run the desktop. That may be a long process another way you could try is install the kde-plasma-desktop package and see if it will replace the lost packages.

sudo apt install kde-plasma-desktop

When you want to update your system at least for the time being I would not use the terminal but the Discover update tool to avoid this problem in the future.
Good luck.

or kubuntu-desktop, which would include kde-plasma-desktop as well as other non-plasma things as well, and might pull in more missing bits.

Can anyone suggest a solution, firstly to get the DE back, and secondly to stop this happening a third time. Perhaps I should just not bothering to update in future?

Don't blindly proceed? And if unsure, copy the lists of the proposed changes.
The system did do what it was told to do, the user unfortunately has to take care before going ahead. it never hurts to wait a bit to see if there is just a temporary logjam, or something, or to note these things and post a question and seek advice.

The 'held back' packages are part of apt's fairly new 'phased' updates feature that Ubuntu is making use of. A small set of updated only go out to a smaller percentage of people at first, before going to the general public.
This most likely has nothing to do with the proposed removals etc that you experienced, but I am sure it is a possibility, though there would be a huuuge number of people seeing the same thing happening.
But seeing the output apt gave you would give us good info to go on as to where to look for causes and advice, in the future.

[SamCaine]

Thanks to everybody for their suggestions, I'll print them all off and give them a try.

If I only use Discover in future to carry out updates does that give me the option to Autoremove, or will I have to live with loads of unneeded files cluttering up my system?

[Snowhog]

Your new (?) to Kubuntu, but even so, I (personally) suggest that you don't use Discover to perform system updates. That's just me however. I don't use Discover. I do use Muon Package Manager, but only to search for things. I don't do package installation/removals/purges or normal system updates/upgrades using any GUI application. All that is done from the CLI. You just have more control doing so IMO.

IF one uses the CLI, then you have the option, when presented with a list of packages being held back, to abort the upgrade if you so choose. Just check again later (same day; next day; when ever) and when no packages are presented to be held back, proceed with the upgrade. Easy Peasy.

[claydoh]

Thanks to everybody for their suggestions, I'll print them all off and give them a try.

If I only use Discover in future to carry out updates does that give me the option to Autoremove, or will I have to live with loads of unneeded files cluttering up my system?

You can use both Discover as well as the command line as it suits you. One could easily use Discover to do regular updates, and to update any flatpaks, snaps, and Plasma theme items installed. Then every so often, run an auto-remove as you feel the need to. it is completely up to you and how you want to do things.

Apt and discover are both installing the software the same way, so it doesn't really matter which one is used to handle the updates. Apt has more features you can access, and it usually is easier and simpler to stick with one tool over multiple ones.

[SamCaine]

Your new (?) to Kubuntu, but even so, I (personally) suggest that you don't use Discover to perform system updates. That's just me however. I don't use Discover. I do use Muon Package Manager, but only to search for things. I don't do package installation/removals/purges or normal system updates/upgrades using any GUI application. All that is done from the CLI. You just have more control doing so IMO.

IF one uses the CLI, then you have the option, when presented with a list of packages being held back, to abort the upgrade if you so choose. Just check again later (same day; next day; when ever) and when no packages are presented to be held back, proceed with the upgrade. Easy Peasy.

Not new, no. I've been using Linux since the 90s on RH initially, though I've been using Kubuntu since it came out. Not a power user by any means, clearly

I'll learn to be more introspective in future.

[SamCaine]

You can use both Discover as well as the command line as it suits you. One could easily use Discover to do regular updates, and to update any flatpaks, snaps, and Plasma theme items installed. Then every so often, run an auto-remove as you feel the need to. it is completely up to you and how you want to do things.

Apt and discover are both installing the software the same way, so it doesn't really matter which one is used to handle the updates. Apt has more features you can access, and it usually is easier and simpler to stick with one tool over multiple ones.

I'll switch to a combination of both to save any future heartache, thanks

[SamCaine]

However, the suggestions have resulted in partial success, but left me with deeper problems.

I did claydoh's suggestion first, which achieved the reinstallation of a lot of files, but still no DE.

Then I used kc1di 's kde-plasma-desktop suggestion which gave me a graphical login screen.

However, I'm left with no keyboard or mouse and this no way to log into the system nor get to a CLI. So, I guess I'm left to do a complete re-install.

I'm sincerely grateful for your help and suggestions.