[SOLVED] no GUI login after upgrade to buster

[Rich]

I recently upgraded my Dell laptop from stretch to buster. I used the old procedure from previous upgrades:
- apt-get update
- backup the computer to another computer with larger drive
- vi /etc/apt/sources.list: change all instances of 'stretch' to 'buster'
- apt-get update
- apt-get upgrade
- reboot and do a few quick checks
- apt-get dist-upgrade
- reboot
The upgrade went well, and I found no problems other than a few missing icons.

I then tried the same procedure on a Dell Optiplex 7010 desktop. This upgrade also seemed to go well, but on reboot the machine produces only this command-line login:

Debian NGU/Linux 10 bench tty1

bench login:

I can log in at this point, and startx will cause KDE to start up normally. But I cannot get the machine to produce the same sddm GUI login that I get on my other machines.

At a root command line, I have tried
# dpkg-reconfigure sddm
which has solved a similar-appearing problem in the past. But this command produces no text feedback, no questions or options. After a few seconds, it simply returns to the command prompt.

I must be missing something simple. Any advice, please?

... Rich

[arochester]

I can log in at this point, and startx will cause KDE to start up normally. But I cannot get the machine to produce the same sddm GUI login that I get on my other machines.

SDDM is a bit buggy. Try LightDM?

[Rich]

A nice, simple fix - and it worked!

Thanks, arochester.

Now for the HARD question .... how do I mark this "Solved"?

... Rich

[4D696B65]

edit the title of your first post