Did you disable UAC, and was the account you were using an administrator?
Question: When you installed the SMP client, did you install "For Everyone" or "Just For Me"?
Just solved my own problem >.<
You have to log into Install.bat with your Main (that would be the first account you made in windows) credentials regardless of the account your installing it in.
Might want to add that in for n00bs like me who don't know better, and want a account without to much stuff running in the background to get the most folding done.