We are trying to upgrade an mvc 2.0 application to mvc 4.0.
This is what I tried
1>Installed mvc 4.0
2>Changed the project to target .net framework 4.0.
How ever when I check the project references, the System.web.mvc being targeted is still version 2.0.0.0.
Do I manually delete these references and add them again?
Yes, delete the references to System.Web.Mvc and re-add them. This is in accordance with the release notes for upgrading from MVC 2 to MVC 3, and the same principal applies going to MVC 4.
(or to v4.0.0.0 in your case)