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I have a Windows 2003 web edition server that I can't seem to get the SMTP relay working.

BT4 shows port 25 open. When I try use telnet to test it on my desktop I get:

  Connecting To XXX.XXX.XXX.XXX...Could not open connection to the host, on port 25: Connect failed.

From the server I get:

Microsoft Telnet> o 25
Connecting To

Connection to host lost.

There isn't anything useful in the logs.

Any ideas?

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Does NetStat show port 25 is open? Is the SMTP service started, is there a firewall installed? – Ed Fries Jan 15 '11 at 1:26
@Ed Fries -- Netstat shows SMTP, Windows Firewall is the only firewall and port 25 is open, the SMTP Virtual Server in IIS is running. – NitroxDM Jan 15 '11 at 5:49
Does it allow connections from any host? What ip/hostname is it listening on? – Tuinslak Jan 15 '11 at 10:50

Windows Firewall doesn't block connections on the loopback. Check on the smtp interface on which IP it is listening first.

Did you try to restart the windows smtp service ? Maybe it's in an invalid state.

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It's listening on (All Unassigned), and it's static IPs on port 25. – NitroxDM Jan 17 '11 at 14:59
Restarting the service hasn't helped. I don't think it's in an invalid state as it relays messages. – NitroxDM Jan 17 '11 at 15:05
do you have any AV on it ? Symantec & co monitor traffic on port 25 for Virus, even the desktop edition – Mathieu Chateau Jan 20 '11 at 18:23
up vote 0 down vote accepted

I have yet to connect using telnet.

However I ruled out iis using smtpdiag.

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