In the dangerous world of Internet e-mail relaying has been a tricky situation in recent years, even though Exchange 2000 and above were defaultly configured properly to avoid being used as mass mailers by 3rd pary mail bombers.
However, sometimes you did need to allow certain elemnts to relay through you. The first one for me was always the backup server, using SMTP to send and recieve messages, then the monitoring infrastracture, then certaing partner companies.
Guess what? This now not really easier but you have more options for controlling relaying with the new Exchange version.
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