[ddouglass]

I don't have Vista or I could go to the site and tell you exactly where to find it. Maybe someone who uses Vista can tell what you need to do to get the custom updates.
Do a search for Belarc Advisor on the internet, download it and run it (Its free). This program will tell you if all the updates are correctly installed or if you need some that aren't. All Microsoft's website can tell you is that you have downloaded and installed it, not whether it actually worked.
The error you are getting means something is missing from your computer that the install program needs to complete it.