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Extensionless URL Rewriting in ASP.NET without using IIS 6 Wildcard mapping

IIS 6.0 Wildcard mapping makes each and every request go through ASP.NET 2.0 ISAPI handler including Urls with .gif, .css, .js, .html etc. So, it suffers from scalability problem. Some research shows that it slows down the performance of web application about 30%.

So instead of using IIS 6.0 Wildcard Mapping or ISAPI Module, i just use HTTP 404 approach.

You must first configure 404 redirection in IIS 6.0, for this you must complete the following steps. Please see the dialog box. Just customize it according to your own requirement.
From Global.asax BeginRequest event, capture this URL and see whether it's an extensionless URL request. If it is, do your URL rewriting stuff for such extensionless URL.