Since upgrading from ASP.NET MVC3 to MVC4 I have run into an issue. The application has a big portion of it's controllers and views embedded into a dll that the main project references and the solution relies on a standard VirtualPathProvider that checks if the requested view exists in the dll and if so returns it.
After upgrading to MVC4 the request for the layout page doesn't go through the VirtualPathProvider anymore, causing the entire application to crash. All of the other views including partial views are handled correctly and are loaded from the assembly.
Has anyone else run into any similar problems after upgrading to MVC4?