GADGETS in the SIDEBAR are NOT VISUALIZED PROPERLY. HELP!!

I'm still having problems with the windows vista sidebar. It was working
fine then
suddenly it stopped working and I can't seem to view the gadgets properly.
They appear either as a blank black or white box.

Any suggestions on how to fix this problem? Or maybe if there is a way to
reinstall the sidebar?

Thanks!

P.S.
I've tryed to do it on the REMESH way,
http://www.winhelponline.com/articles/208/1/
but still the same. Somewhere I read about some .DLL files removed when
installed NERO.
Anybody knows which are those, and where to download those missing files?
Thanks for helping me!