Reference to System.data.entity.design.dll not working

I'm working with a new Entity 开发者_如何学JAVAFramework repository and need System.data.entity.design.dll for using the PluralizationService. Now when I go to add reference, it wont show up in the ".Net" tab. Also if I go to: ..\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework\v4.0 and add the dll from there it won't fix my namespace using and will only create a yellow icon at the dll in the reference folder.

Does anyone know how I can fix this, or even where to download the dll again?

Change the target framework of your application from .NET Framework 4 Client Profile to .NET Framework 4.