Office 2007 Help Viewer quits and does not work with any applicati

I have Office 2007 running on Vista Home Premium. Whenever I use any of the
programs in the suite and try to go to the help feature, the "Microsoft
Office Help Viewer Has Stopped Working" dialog pops up and the help window
closes. This is especially annoying in excel where i need help with some
formulas.

Any ideas whats wrong and what I can do to fix it?