I think you are running into a permissions issue with the Vista zip application (the one that's built in). Vista hates to allow people to write anything into the Program Files area and if that is where you have defined your PC Gen datafiles to go, then you might have problems. I'm not sure of the exact procedure to change the behaviour, but you can adjust the settings on your Vista account to allow you to act as a true Admin on the machine and to remove the additional Program Protection that it uses.
Hope this helps.
--- In firstname.lastname@example.org, "Thomas" <shinjo69@...> wrote:
> I can install and run PCGen in Vista, but when I try to install one or the other of the new pathfinder rpg datasets, it says it cannot creat pcgen/data file, and the install fails.