Why is System.Web.Mvc not listed in Add References

Question

Using C#, Visual Studio 2010.

There is a namespace called System.Web.Mvc documented on MSDN. The documentation for all the types in that namespace says that they are in System.Web.Mvc.dll.

However, when I go to Add Reference, “.NET” tab, this assembly is missing from the list. Why?

Answer 1

Best way is to use NuGet package manager.

Just update the below MVC package and it should work.

Answer 2

"OK, adding that XML to the Web.config works, but it doesn’t answer the question"

It should be there. By default the add references list seems to be ordered, but its not the case. Hit the name header and look again.

Answer 3

I have had the same problem and here is the funny reason: My guess is that you expect System.Web.Mvc to be located under System.Web in the list. But the list is not alphabetical.

First sort the list and then look near the System.Web.

Answer 4

I believe you'll find the MVC assembly is referenced in the web.config file, not in the project itself.

Something like this:

<compilation debug="true" targetFramework="4.0">
  <assemblies>
    <add assembly="System.Web.Abstractions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
    <add assembly="System.Web.Routing, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
    <add assembly="System.Web.Mvc, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
  </assemblies>
</compilation>

To respond to your comment;

The best answer I can give is from here:

The add element adds an assembly reference to use during compilation of a dynamic resource. ASP.NET automatically links this assembly to the resource when compiling each code module.

Answer 5

Check these step:

1. Check MVC is installed properly.
2. Check the project's property and see what is the project Target Framework. If the target framework is not set to .Net Framework 4, set it.

Note: if target framework is set to .Net Framework 4 Client Profile, it will not list MVC reference on references list. You can find different between .Net Framework 4 and .Net Framework 4 Client Profile here.

The .NET Framework 4 Client Profile is a subset of the .NET Framework 4 that is optimized for client applications. It provides functionality for most client applications, including Windows Presentation Foundation (WPF), Windows Forms, Windows Communication Foundation (WCF), and ClickOnce features. This enables faster deployment and a smaller install package for applications that target the .NET Framework 4 Client Profile.

Answer 6

If you got this problem in Visual Studio 2017, chances are you're working with an MVC 4 project created in a previous version of VS with a reference hint path pointing to C:\Program Files (x86)\Microsoft ASP.NET. Visual Studio 2017 does not install this directory anymore.

We usually solve this by installing a copy of Visual Studio 2015 alongside our 2017 instance, and that installs the necessary libraries in the above path. Then we update all the references in the affected projects and we're good to go.