Error "At least one display must be active"

I’m running OpenSUSE 11.1 and just upgraded from KDE 4.1 to KDE 4.3. Unfortunately YaST – which worked fine before – fails to cooperate and whenever I try to change anything, e.g. my keyboard settings, gives me the error message “At least one display must be active”. Well, what does that mean? Of course, I have an active display and I also included the repositories for the NVIDIA graphics card.

Thanks in advance,

Did you do a full upgrade?

zypper dup