I\'m running Windows 7 Ultimate (64 bit) using Visual Studio 2010 RC. I recently decided to have VS run/debug my apps on IIS rather than the dev server that comes with it. <
Adding another solution for this issue.
in my Global.asax.cs file I had disabled attempted php files from being consumed by the MVC pipeline using the following:
routes.IgnoreRoute( "{*php}" );
I had done these previously in a MVC2 project and it worked fine, but doing this in my MVC 3 app caused the issue reported above.