Here is an example, see how the subdomain part is captured and then used to rewrite the URL: http://learn.iis.net/page.aspx/468/using-global-and-distributed-rewrite-rules/ By searching http://www.bing.com/search?q=subdomain+rewrite+site%3Aiis.net First result was: http://forums.iis.net/t/1155754.aspx...