This is a similar question somone asked a few years ago: ‘Cannot start OpenSuse 11 after changing to Metacity’ from 09-Jul-2008. But non of the suggestions given there worked for me.
Last week I upgraded to 12.3 from 12.2 though internet. Everything worked perfectly. Then two days ago I tried to log in to Metacity, unwisely without resetting the auto log in option. This resulted in a black screen and only a cursor. Through ctr-alt-f1 I tried to change login settings through command line. But I am unable to open /etc/sysconfig/displaymanager. I alsotried init 3, kdm; no result. I have also tried to change settings in root - yast. I get to configuration options - desktop- etc/sysconfig editor. Somehow it does not show the editing options.
I have also tried to change settings using a Kubuntu live cd. But it does not allow to save changed settings in the displaymanager file. I wat thinking of trying to change settings with a new USB bootstick. The new 12.3 requires UEFI enabled but sofar I habe been using BIOS. I am not sure what the consequenses would be if change BIOS to UEFI and feel a bit uncomfortable about this.
Does anyone have any suggestions how I can change back to login screen? Otherwise I will have to reinstall all again.
You might try and disable non standard repos and retain repos (oss,non-oss,uodate and non-oss update) and do a zypper dup and restart.Hopefully the setting might go away. Did you remove kdm or something ?
Read of UEFI here openSUSE:UEFI - openSUSE Wiki.
