I've just watched the video from ITIdiots on installing and configuring Exchange 2007.
Exchange IS delivering email WITHIN the organization (tested with two separate accounts), but is not delivering to or receiving from outside of the network. This suggests that it would be a possible firewall issue. On my router (linksys), I have SMTP (:25) mapped to my Exchange Server.
I'm using DYNDNS.ORG for my domain resolution to my local router, with no MX server (defaults to my domain).
When I run the troubleshooting assistant, and generate the report, the error it gives me is: "messages could not be delivered with delivery status notification code '4.4.7'."
I use Comcast (residential) for my ISP, so I'm wondering if this has anything to do with the issue. The ITIdiots guys had the same setup, (including VMWare based machines), with the exception of Comcast.
Is there anything I can do to get this working? I understand the concepts, but first want to ensure that it works, before I continue.