无法加载文件或程序集的System.Web。Mvc, Version=3.0.0.0, Culture=中性，PublicKeyToken=31bf3856ad364e35'或它的一个依赖项。

I downloaded the web app from my company's server and running it on my machine. It works well except when I click on one of the menu items (all the others are good). It is showing me this error. I checked my web.config and the version I set for web.mvc is 4.0.0.0. I have no idea how is this happen. I downloaded the web app from my company's serv