Is port 445 now locked? This port is essential for establishing trust between two Active Directory domains.
Why are you trying to route port 445 over the public Internet? You should setup a VPN/MPLS/Layer 2 connection instead.
Actually, now that I saw what I posted in the wrong forum. Please move to the forum Tunnelbroker.net Specific Topics. In fact it has nothing to do with DNS.
Regarding the need, as initially reported, port 445 is used to establish trust relationship in Active Directory, as well as authentication of users and computers.
Only IRC & SMTP are filtered until Sage access when the filters can be removed.
Solved. Problem detected on a specific server.
Thanks.