We have set up Exchange 2010 that contains all the roles. We also have Forefront TMG server installed to our DMZ with NIC's to LAN and Internet.
We are able to access OWA logon screen from Internet but the authentication fails with error "Unable to logon to Forefront TMG. Make shure that the domain name, username and password are correct and try again.".
From LAN I get error that the page can not be displayed.
In TMG the listener settings are: HTML Form authentication, Windows (Active Directory). I have single network "Perimeter" with Specified IP Address. The address is static and set to a NIC pointing to external network dedicated only for this.
In Client connection type I have selected "Enable SSL (HTTPS) connections on port: 443". In Certificates we have selected to use a single certificate for the listener.
The OWA policy Authentication Delegation is set to Basic Authentication. Rule applies to all authenticated users.
I have gone through different scenarios about setting up Exch 2010 with TMG but can't get the authentication to work.
We have multiname unified communications certificate from Digicert set up to Exchange and TMG servers.
Could you please provide some pointers on where to start looking for the problem?