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cybersst

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Exhange 2000 won't receive messages after an IP address change

I changed the IP address on my Exchange 2000 server and now it won't receive messages from external domains.  Internally it works fine.   It will send and receive internal emails, and send external emails.  It has a hard coded IP address and was able to be pinged after the address change.  I also restarted it after the address change.
One other symptom it had is that it would not accept a telnet session after the address change.
I gave up trying to fix it and set the IP address back to the original address and now everything's working except I still need to give it a new address.
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tigermatt
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Is this the internal address or external IP address we are talking about?

If it's the internal IP address, then you need to change it on your firewall configuration too. You'll need to look for a configuration which is allowing port 25 through the firewall, and change the configuration of this firewall rule so that the internal IP address to forward the traffic to is the NEW address of the Exchange Server.

If you have changed the external IP address provided by the ISP, then you need to go to your ISP/domain registrar, or the company which hosts your external DNS if it's neither of those two companies, and request your MX record is updated to match the new IP address.

-tigermatt
I believe you should be able to telnet to port 25 after changing the Ip address internally, but not externally. right?

Tigermatt is right. I believe the firewall is still forwarding emails to your old IP so you need to change the IP settings on the firewall too, to reflect the changes. So once you change the firewall configuration to send all the emails to the new IP address then you will be able to telnet to this server from the internet.

Which firewall is it? Are you using NAT for it?
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cybersst

ASKER

I changed all the settings on the firewall.   In testing the server by telnet I was doing it inside the firewall so even if the firewall settings were wrong it would have no effect on the telnet test.  It was the internal address that I changed.   I also made sure the the changes were reflected in DNS.  I have a hunch the answer may lie with Active Directory.  I'll  be taking a look at some of the command line tools like dcdiag or nslookup.
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RajarshiVaibhav Pandey
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What happens if you try from a station outside the network to telnet into the static external IP on port 25? Can you get a connection? Then, if you can, try it with the MX record domain - and see if you get a connection then.

Post the results.
I'm using a gateway on another server that caches the incoming email and quickly relays it to the email server.  That's how I knew it wasn't working...it has a window that displays incoming and relayed email in real-time.  From looking at the window I can see that it's accepting the incoming mail so there's no issue with the MX record or any other external configuration.

Kunalclk.. I'm not sure what you mean by "SMTP Virtual server" tab ,but I checked the properties of the SMTP connector and verified that there are no restrictions.  I have documents from when I set up the server and I'm sure that there are no references to any external IP addresses other than a DNS address that's external to the network.  It just sits there and accepts any email coming in to the domain.
addendum to previous comments

Concerning the gateway I meant to say that the real-time window shows the incoming email, but doesn't show it being relayed to the email server as it always does when everything's working.

FYI.. I'm using Trend Micro's Internet Messaging and Security System on the gateway.  I had the tech on the phone to troubleshoot the thing and that's when we noticed that the email server just wouldn't allow a telnet session, which explains why the emails weren't being relayed.
Without delving too much into the gateway - which I have no knowledge of - can you check anywhere on the gateway whether the old IP of the Exchange Server is configured there?

Also I would recommend you check also on the internal DNS - you might throw something up there.
I checked the IP address in DNS..also the address on the gateway.  So far I have a total of 3 locations where I changed the IP address

1. On TCP on the NIC
2. DNS
3. Gateway

The gateway doesn't matter at this point.  The main thing is getting the mail server to listen on the new ip address.  The fact that telnet won't connect from an inside workstation after the address change is probably a symptom of the real problem.
Exchange doesn't listen on a specific IP address. What are you telnet'ing to from inside, the internal or external IP of the Exchange server?
Aplogies for not responding sooner.  I  checked the SMTP VIrtual Server properties on the General tab and found that it was set to the old IP address.  I think it may have been a default settting because I don't have a record of changing it.  Kunalclk was just one tab away from being right.   Thanks.
The settings of the properties on the SMTP virtual server were at fault.  The correct location of the error was on the General tab, not the Access tab.