IIS Error: Unauthorized: Authorization failed by an ISAPI/CGI application. Internet Information Services (IIS)

I receive this error message when browsing to the Nerve Center

HTTP Error 401.5 - Unauthorized: Authorization failed by an ISAPI/CGI application. Internet Information Services (IIS)

or

HTTP Error 401.3 - Unauthorized: Access is denied due to an ACL set on the requested resource. Internet Information Services (IIS)

See:

http://support.microsoft.com/default.aspx?scid=kb%3Ben-us%3B906474