Cassini can be very misleading. For example, spin up web site that uses routing in Cassini and it works without a problem. Do you have to add the routing module or handler? Nope. It just works. It’s so nice and helpful, but that really gives you a false sense of security.

IIS is not so nice. We recently ran into this where things worked great in Cassini, but as soon as they were deployed to IIS, nothing routed. It turns out we were missing a bit in the web.config that enabled routing.

I just stole that section from a newly created MVC 2.0 application’s web.config.