The type 'Expression<>' is defined in an assembly that is not referenced

Question

In ASP.NET MVC 4.5.2 Framework.

after typing

@Html.LabelFor()
or 
@Html.EditorFor()

in view

I\'m getting Error: The

Answer 1

In my case the solution was to move the ConnectionString inside the Web.Config. This statement should be after AppSettings section.