Getting Access is Denied when browising page over HTTP

  Hello I have a sub-ordinate CA which users connect to request certificates. The website is configured to use SSL certificates. Things are working fine when they connect over usinghttps://server_name/certsrv however when any user connects usinghttp://server_name/certsrv they get a "403 - Forbidden: Access is denied." What they should be getting is a page displaying "HTTP Error 403.4 - Forbidden The page you are trying to access is secured with Secure Sockets Layer (SSL)." Also one thing I have noticed is that if i try to connect to the website using http on the web server itself then it does not give Access Denied message.

Any help on this would be appreciated :)