ASP.NET MVC2 instant 404 Errors

I have a ASP.net MVC2 website that was working great when using Visual Studio 2010 RC But after installing Visual Studio 2010 Ultimate, i have been seeing nothing but 404 errors from my mvc website.

I'm pretty sure it actually is a MVC2 app, but after reading around i'm getting confused. But how that could result in the 404 errors im getting now, i dont know.

The problem occurs when开发者_如何转开发 trying to debug the website from visual studio.

Any ideas? Thanks in advance :)

I fixed the 404 errors by removing the System.Web.MVC Reference and then adding it...