I've followed the steps to setup ASP.NET routing here: ASP.NET Routing… Goodbye URL rewriting?
I'm on IIS5.1 (yeah, i know) so I had to do the "Wildcard Application Mapping". And now my IIS DefaultDoc "default.aspx" is giving a 404.
I can see other people with the same problem here and here, but no solutions.
David Wang makes it sound like I'm out of luck. Now I'm investigating UrlRewriter.NET.
UPDATE: My dev enironment is XP+IIS5.1, the production & staging servers are windows-server-2003+IIS6. The problem only occurs in IIS5.1, so I figure I just put up with it in dev.