Ok so I go to my modtools folder and click on the XSI folder. It then tells me that my computer can not open the file because it does not have the right software, and asks me if I want to search the web for it, which doesn't help. What do I need?

Wait, you're clicking on PandemicBF2.xsiaddon and trying to run it? Nope, thats just an addon for the XSI program. Hence the file extension .xsiaddon

Getting the program itself can be found in the stickies in this forum.

Ok gotya. Mods, lock this up please.