And also, do you have WSUS installed? I think you may need to install the base version of WSUS before you can install SP1. Or there may be a different file that you can download (which is the entire WSUS product with SP1 integrated).

http://www.microsoft.com/downloads/e...&stype=s_basic (Some links to related content at Microsoft)

I would check to make sure that you have all of the prerequisites before you try the installation again.

Have a great day
Patrick.