When I try to send outbound email through my Edge Transport server through telnet I get an error in the logs for any external addresses I get an error 550 5.7.1 Unable to relay. Interanal addresses work fine though. I also get this from an application that I have that sends out error messages through SMTP. I am trying to phase out our IIS SMTP server and have this traffic sent through the Edge Exchange server. Here is an example of what i get in my logs:
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