I have a .NET 3.5 Web application on VS 2008 SP1 running on Vista Ultimate 32 SP1. I created an Application under the Default Web Site. So the url to the app is \"http://localho
open IIS7 (run > inetmgr) and go to the Feature view. Open the ISAPI and CGI Restrictions section and check if your .Net version has the correct restriction (for example, if you're working with 4.0 is should be on "Allowed")