http://msmvps.com/blogs/shahed/archive/2009/05/17/asp-net-mvc-tips-301-redirect-non-www-versions-of-url-to-www.aspxSearch Engine Optimization guides, recommends to have one version of a URL of the same content. Search engines may pickup www and non-www versions of URL as 2 separate URLs, i.e. http://xyz.com/page1 may be considered different to http://www.xyz.com/page1enCommunityServer 2008.5 SP2 (Build: 40407.4157)