Our Exchange has been installed on load balancing environment (2 HUB/CAS 2007 servers) and clustered mailboxes (2 mailboxes) all servers is running Windows 2008, all exchange servers are behind of ISA server , and the ISA server has been configured to display a login form to authenticate user, the two CAS sever have been configured to use basic authentication.
let say the url for accessing the mail is mail.company.com
The following case appears on one of CAS server (if it is up) ,
when any one wants to access his mail by typing http://mail.company.com
he will get the below error before entering his credentials:
403 - Forbidden: Access is denied.
You do not have permission to view this directory or page using the credentials that you supplied.
But when he access mail by typing OWA after url (http://mail.company.com/owa
) , the user will be asked to enter his credentials.