New Post: Prism Quickstart gets "The remote server returned an error: (407) Proxy Authentication Required." error when compiling

I downloaded the Prism 5.0 from the link (http://www.microsoft.com/en-us/download/confirmation.aspx?id=42537). I installed it. I'm trying to build/ run the BasicMVVMQuickstart_Desktop. The build gets the error "The remote server returned an error: (407) Proxy Authentication Required."

This seems really odd to me. Why would a build be trying to connect to something? Anyone have a solution to this problem?