Hi!
I changed some settings in user options in YaST2, i.e. “Cancel user entrance to system”,
and I can’t enter my system anymore. Tried different boot modes (safe, IceWM) - console says “Wrong user name”. :’(
What to do?
At the login screen hit Crtl+Alt+F1. Now you can login to a console session, i.e. a nongraphical session. Do that, as “root”.
Then type ‘yast’ to start YaST with the ncurses interface. Undo your damage (<-- OK, that sounds a little bit hazy, but I guess you know best what exactly you did).
Hit Crtl+Alt+F7 to get back to the graphical login screen. Login as you.
If that works, hit Crtl+Alt+F1 to get back to the open root session and close it (‘exit’).
How do I enter root session? It doesn’t accept my login. Which login to use?
Username for root is “root”. 
Password should be the same that you used to start YaST2.
But make sure it is a non-graphical session. Warnings against GUI logins as root are plenty.
thanks a lot! it just works!))