When is a ASP.NET Project Not an MVC Project?

I am working on a hybrid ASP.NET MVC and MVC Dynamic Data project. To work on it I started with the MVC Dynamic Data project assuming this would be a Dynamic Data Project and an MVC project. As Scott Hanselman recently posted, you can mix and match pretty easily so the code was working but I was missing an important piece of functionality in Visual Studio:

My project wasn’t being showing these items (or other menu options specific to MVC apps). I suspected it was some magic in the project file so I opened it up in my favorite editor:

<Project ToolsVersion="3.5" 
         DefaultTargets="Build" 
         xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <PropertyGroup>
    <Configuration Condition=" '$(Configuration)' == '' ">
      Debug
    </Configuration>
    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
    <ProductVersion>9.0.30729</ProductVersion>
    <SchemaVersion>2.0</SchemaVersion>
    <ProjectGuid>{F7526D86-12B4-434F-8355-20592CFC4937}</ProjectGuid>
    <ProjectTypeGuids>
      {603c0e0b-db56-11dc-be95-000d561079b0};...
    </ProjectTypeGuids>
    <OutputType>Library</OutputType>
    <AppDesignerFolder>Properties</AppDesignerFolder>
    <RootNamespace>Foo.Web</RootNamespace>
    <AssemblyName>Foo.Web</AssemblyName>
    <TargetFrameworkVersion>v3.5</TargetFrameworkVersion>
  </PropertyGroup>

The missing bit was a special ProjectTypeGuid: {603c0e0b-db56-11dc-be95-000d561079b0}. You need to add this to the existing ASP.NET project’s ProjectTypeGuid list in the project file and magically the project item types appear.

HTH