If you indeed have SP1 on vista that should be okay. You are sure that SP1 is correctly installed?
One other small thing.. are you running it as administrator?
Also try setting the compatibility to another OS, like windows XP and not 2000, that has helped some folks, and if your error speaks of XP SP3, it might be an indication to run it in XP SP3 compatibility mode.
Or it can also be the other way around, in which case make sure that it's actually set to your own OS, Vista SP1, and NOT something else. Some users need to set it to their OWN operating system, because for some reason it's not set to that by default.