I have an exchange 2010 server running on Windows 2008 R2, I also have a remote webserver running Windows 2003 with multiple sites on it (all asp.net mvc 2 sites). I setup a Transport in exchange and all the websites on my remote web server can send email no problem to anyone in the exchange server and to any external domain.

Now for my problem. I am having issues with that webserver, so I moved one of the websites to run on my exchange server, it runs well (low hit website) except that email doesn't work from that site. I tried changing the Transport in exchange to add the IP address of the local machine and the 127.0.0.1 addresses and it still isn't sending any email.

Any ideas on how to get this working?

The remote websites can still send email no problem, the version of the site that I had to move on the remote server can still email, but on the exchange server for that website email does not send.

I would guess it is a Transport issue, since it is running on the same server a firewall shouldn't be the issue.

I changed the smtp setting in web.config to localhost, and now I do receive email to my account on the exchange server, but I do not receive any emails on outside addresses.

To add more description, this is a custom developed asp.net mvc 2 website. And no errors were being generated in the code when sending the email in either case.