Probably the single most common issue I have had with linux of any distro is mysteriously vanishing GUI and/or login . I will install , then 2 or 3 months pass, then tinker with an update or try to change a look'n feel in KDE, or add a user, then all of a sudden, I have lost GUI completely and/or the login goes to a graphical root or login has changed.

Personally this has plagued me throughout several distros, and is probably due to my tinkering. Since I generally backup my /home folder it has been easier to reload OS, but sometimes the KDE config files get screwed up and reinstalling OS does NOT help.

Tried using boot floppy, but I think it's reserved for instances where you cannot boot into the system.
I can boot, just not into GUI

Anyway, what would be the most important system and / or KDE configuration files to back up and generally where are they found? I guess they are in different places in different distros.

If someone could point me to a tutorial , please

thanks

Does this mean you have just console and no X? If this is the case, look at /etc/X11/XF86config or whatever X are you using. Can you log in on console and run 'startx'? Can the other user log in and use X?

Is your graphical login manager working? Can you choose a failsafe mode?

Best,
Ott

otoomet is probably hitting the nail on the head. Sometimes trying to make 3d accelleration work or using the wrong video driver can cause X to not start for any user.

If it's not your xorg.conf at fault, and you say no users can load X then check the gui's global config files. For KDE it's usually /opt/kde/etc or share. Have you tried loading a different gui to see if that's it? From a command line try the strtfluxbox command. If it starts it could be KDE settings and not Xorg.

Sometimes I am just in the shell, I don't know if that's considered a console per se.

Yes, generally if I hit startx I get error messages such as:

font not found
or
no screens found
or
x could not connect to server

This last time, if I chose 'linux' I could boot to graphical login, but system would not take passwords no matter what.
Then I booted into failsafe which I guess is a shell. Tried startx but got 'no fonts' , so transferred some files via CL to a FAT partition.
I have currently reloaded OS so there are no problems, but I think I will start to backup these files.

Thanks