Mac newbie Q: Port 25

[XX621]

Hi All
I'm trying to set up my iMac with an SMTP server I used to run on Windows (got sick of the virus/crashes/slowness general unreliability of Windows).

Setup gone well, the SMPTP server responds from a telnet on port 25, but external clients get "connection refused". My router port 25 is open and directed to the iMac, and my ISP allows port 25. I am at a complete loss as to what to try next...have checked MX records - they are all correct.

Is there any Mac diagnostics/utils I can run to find out why it is not picking up external TCP connections on port 25?

The logs of the SMTP server indicate no connection attempts.

Any help ideas would be greatly appreciated - I am well and truly stuck!

The network interface, of the SMTP server, is set up to listen to all network interfaces on the iMac, by the way.

Steve

[Satcomer]

Post 25 is the SMTP port but most ISPs block port 25 beyond their email servers in a vain attempt to stop spamming on their systems. If you are trying a email server beyond your direct ISP try email SMTP 587.

[ngcomputing]

Try port 26 too. I had a client on Embarq which was blocking port 25. If all else fails, you can always go with IMAP.