That was indeed the issue. Thank you Victor. For anybody else wondering, there's a good article about developing with UAC.

http://windowsteamblog.com/windows/b...direction.aspx

We were able to help the customer and we're now going to make sure that our apps are UAC aware (something that I've wanted to do for a long time now). Looks like it's time to finally bring our app up to speed with a feature that came out in 2006.