Hi, we are running exchange 2003 on one server with mail_Relay on IIS on another machine this all work fine. We have a customer who runs exchange 2007 and wants us to use TLS with them. on the Mail_relay how do we enable TLS to just this one cusomer (inbound and outbound)while leaving mail flow as it is to all othersPLEASE HELP...as much details with the config would be great

Its not so easy in Exchange 2003:http://msexchangeteam.com/archive/2006/10/04/429090.aspxImplementing TLS between two Exchange Server organizationsAlternatively, upgrade to Exchange 2007 which supports opportunistic TLS or use a 3rd party SMTP gateway that supports it ( IMSS, Tumbleweed, A hosted service. etc...)