System.Data.Entity.DbContext can't find to add as a reference

Question

When I go to build my project, I get this error:

The type \'System.Data.Entity.DbContext\' is defined in an assembly that is not referenced. You must

Answer 1

1. Go to the Solution Explorer
2. Right-Click on References -> Manage NuGet Packages...
3. Select Online-> Microsoft and .NET Click
4. Click Install next to .Net EntityFramework

Answer 2

1. Select the project which throws this error
2. Go to the menu View -> Other windows -> Package Manager Console
3. Make sure your problematic project got selected in the default Project" drop-down in the PMC console.
4. then type the command "install-package entityframework -version 5.0.0.0"

It should install the missing version.