Inalign's Blog

Additions you make in the web.config file, such as redirecting 404’s, will work for all files that go through the .NET engine, but not for other files like htm, html, and directory requests. For these, you have to modify IIS in the ‘Custom Errors’ tab under Properities of a website. You can set the ‘404′ entry to the .NET page that is receiving 404 errors (should be the same one you set in your web.config).