If your portal is running on Windows Vista, Windows 7 or Windows 2008 Server under Asp.Net 2.0/3.5 you do not need to make any manual changes to Internet Information Server 7.0 or 7.5 configuration if the web site application pool is running in "integrated pipeline" mode.
If you run your DNN under Asp.Net 4.0 please see this page
To use extension other than standard .aspx or no extension at all please go to module options and click on the button "Enable Run All Managed Modules For All Requests" on Globals tab in IIS7 Additional Settings section (see the image below).
