Switch from POP3 to Exchange

[JayIT]

Hi,
I need a little help setting up exchange for external email use. right now, exchange is setup for internal email only, and each outlook client has a POP3 account for external email set as primary and Exchange as secondary.

Running Windows 2003 Server. We want to eliminate the POP3 accounts and host our own email server.

Any step by step, links or help of any kind would be greatly appreciated.

 

[58sniper]

Create an "A" record for your public IP address, such as mail.domain.com

Have your ISP create a reverse DNS entry for your public IP address. Make it match the above (mail.domain.com)

Verify that port 25 is forwarding through your firewall to your Exchange server. Test it from the outside by telnetting to your Exchange server:
telnet mail.domain.com 25
and see if you get a response.

Make sure the FQDN configured in your SMTP connector matches the above (mail.domain.com)

Change your MX record to point to the "A" record created in the first step.

After a couple of days, kill the POP3 config and the external mailboxes.

It's early for me, so I might have missed something, but that seems to be all you need.

Pat Richard, MCSE MCSA:Messaging CNA
Microsoft Exchange MVP

 

[JayIT]

ok, for the steps "Create an "A" record for your public IP address" and "Change your MX record to point to the "A" record created in the first step", that's done on the exchange server under Administrative Tools, DNS, correct?

 

[Topkapi]

That's normally done by your ISP, as indeed is the later changing the MX record to point to the A record step.

Hope that helps

 

[JayIT]

The ISP did create the reverse DNS entry for my mail.domain.com. I setup my firewall but when I telnet or when I do an online MX lookup for mydomain.com, it comes up with the hosting company (that is hosting our emails) servers.

So if I understand right, I need to contact back my ISP, ask them to create an A record for my public IP and ask them to change the MX record to point back to that A record?

If I do that, the POP3 accounts in outlook that point back to the current hosting company should still work… correct?

Thanks again for all your help.

 

[Topkapi]

Your ISP may have created a reverse DNS entry but probably that relates to their server(s). I would contact them again.


Yes, the POP3 accounts should still work after the MX record switch but as the effects of the this DNS change propagate over the internet you should see less mail arriving in these accounts and more arriving directly at your Exchange server.

 

[58sniper]

That's normally done by your ISP, as indeed is the later changing the MX record to point to the A record step.

That's actually done by whomever hosts your public DNS. That could be your web hosting provider, you, etc.

Pat Richard, MCSE MCSA:Messaging CNA
Microsoft Exchange MVP