need help to access my machine after upgrade -- system immediately logs me out

Hello,

 

 I need to access my desktop local machine after I did a sysupgrade -s (I had reasons to do so because some rust libraries were too old for some applications).

Sysupgrade seems to have gone fine. Disk is healthy no issues reported.

However when i tried to log from the console -- the login message shows but the system logs me out immediately.

On the desktop gui too, with only root I was able to login. But running xterm from the fvwm menu fails.

I am a bit clueless as to how to gain access to the system.

Some help would be great.

-S