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My mail server is not getting or processing incoming e-mails. I recently changed my MX record to point to a different router on my network. I opened port 25 on the router and pointed it to my mail server. No external e-mails are hitting it. NETSTAT is showing the traffic reaching the server but it times out. Example: TCP ML310DC:smtp TIME_WAIT 0

I know E-mail is working on the server as internal e-mails are being processed.

I have exchange 2003.

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closed as not a real question by Michael Hampton, EEAA, rnxrx, Magellan, jscott Nov 1 '12 at 15:49

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.

1. Verifiy that the MX record points to a valid A record. 2. Verify that the A record resolves to the correct ip address. 3. If 1 and 2 check out then attempt to establish a telnet connection to port 25 of the MX record from outside your network. – joeqwerty Oct 31 '12 at 19:46
What do you mean a valid A record. I have it pointing to a static IP on my router. I cheked it with Remote connectivity analyzer and got the following: – UpTooL8 Oct 31 '12 at 19:53
Test Steps Attempting to resolve the host name in DNS. The host name resolved successfully. Additional Details IP addresses returned: Testing TCP port 25 on host to ensure it's listening and open. The specified port is either blocked, not listening, or not producing the expected response. Additional Details The connection was established but a banner was never received. – UpTooL8 Oct 31 '12 at 19:55
MX records shouldn't point to ip addresses, they should point to A records. Your test would seem to indicate that connections to port 25 of the server are blocked. Are you sure that you have connections to port 25 of the router's ip address forwarded to the server? – joeqwerty Oct 31 '12 at 19:59
Also, what is the domain name in question so that we can test your DNS? – joeqwerty Oct 31 '12 at 20:00

The specified port is either blocked, not listening, or not producing the expected response.

This means that connections to port 25 on your external IP are not working.

One or more of the following could be wrong:

  • You didn't do the port forwarding correctly
  • The SMTP service on your Exchange server is not running
  • You have IP filter rules on your SMTP service
  • The firewall on your Exchange server is blocking SMTP
  • Your ISP could be prohibiting you from running an SMTP server (which is common if you are using consumer class broadband)
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1) Port Forwarding is configured correctly. verified via online port checker. 2) SMTP IS running on my server. Nothing changed on it since I switched routers. 3) No filters on my SMTP services exist. 4? no firewall rules are on the server. My ISP is blocking nothing. We have business class connectivity. – UpTooL8 Oct 31 '12 at 20:15
Back to #1: Your comment above says the SMTP check tool you used said the port is closed. – longneck Oct 31 '12 at 21:09

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