How do I setup Exchange 2007 to receive SMTP mail from DMZ Server

You can bypass your edge, but it would be far quicker to send directly to your Edge server.

If your web server is sending to external people then it will either need to authenticate with the Exchange server or be allowed to relay:
http://exchangepedia.com/2007/01/exchange-server-2007-how-to-allow-relaying.html

I think we may have found the problem.  The web programmer is sending the email to an Exchange 2003 server address and getting hit and miss results (we currently have two email servers in our domain which we are in the process of migrating everyone off of one.)  Occationally, more times than not, a permissions error will occur.  I will have the programmer change the routing IP to the EDGE transport server, and check the results.

Ok. If the app is sending to external it must authenticate or be allowed to relay. If it is just sending to internal then no additional exchange config is needed.

Okay.  So, I'd like to run the email from the web server thru Edge transport.  I had the programmer direct the mail to the IP address of the Edge.  The email ends up in the black hole.  Not bounce back messages.

Is the program sending to internal users or external?

According to my programmer, it is both.

If it is sending to external then the app will need to authenticate with Exchange or be allowed to relay.

Forgive my ignorance.  Is relaying something that needs to be turned on, on the Exchange server or the Edge Transport?

Whichever server requires you to open less ports in the firewalls. Follow this article:
http://exchangepedia.com/2007/01/exchange-server-2007-how-to-allow-relaying.html

My apologies.  I have not been able to get back to this issue and will be out for a week.  It's up to you, whether you want to close this issue or leave it open for a while. Whatever's best. Thanks!  

Leave it open

I'm back, so hopefully I can get back on this project. Thanks.

No problem

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