windows media centre

I have over the weekend had to re-install vista i.e. first to home premium
and then to ultimate. In Home Premium, Media Centre worked well without any
problems. However, when I attempted to run it in Ultimate I recieved the
following error message "windows media centre update manager has stopped
working and will be closed". I have tried it with my firewall etc. off, but
to no avail. I have been unable to locate anything which covers compatible
ground with my error.
I can only assume that a file has been corrupted somehow or other, along the
way. The thing is driving me tp distraction any advice would be gratefully
accepted. I would however ask anyone to bear in mind that my knowledge of
windows in particular and computing in general is on the sketchy side of
basic.