CS0234: Mvc does not exist in the System.Web namespace

Question

I converted a ASP.net 4 webform project to Asp.net MVC4 according to Chapter 13 of the Professional ASP.NET 3.5 MVC, by Scott Hanselmen, Phil Haack, and Rob Conery, Publishe

Answer 1

I had this problem, but all the applications in IIS were broken when they had been working previously. None of the marked solutions helped me. The problem ended up being an extra copy of web.config had been introduced to my root directory. I removed that file and problem solved.