My Server Has Dynamic IP Address, How to Build Internet Mail Server?

[1] My server has a dynamic Internet IP address.
[2] I have an Internet domain.

If your server connects to Internet via ADSL, your server should have a dynamic Internet IP address. You can, but no suggested, build your mail server with a dynamic IP address. Because some other mail servers will reject mails from those mail servers with dynamic IP address for anti-spam protection.

This case is suitable for product trial And you can change to fixed IP address after trial finished. Followings are instructions for building a mail server with dynamic IP address.

Let's assume that your domain is "", your server's local IP address is "" and Internet IP address is 123.123.123. There will be three major steps for you to build up this Internet mail server.

Step 1. On your mail server, you need to do:

  1. Install AA Mail Server ready on your server. Refer: Install AA Mail Server.
  2. Create a domain with "Standard mail server" mode. Refer: Create domains.
  3. Create accounts for your staff. Refer: Create accounts.
  4. Open 25/110/80 TCP ports in your firewall. Refer: Configure firewall.
  5. If behind a router, goto router's panel to create 25/110/80 ports forwarding. Refer: Configure router.
Now your server is ready for LAN mail service (not available for Internet email communication yet). You could verify it with telnet DOS commands manualy on the server:

[1] "telnet 25": verify if AA Mail Server run ready.
[2] "telnet 25": verify if mail service is ready for LAN; if not, check firewall settings.
[3] "telnet 25": verify if mail service is ready for Internet; if not, check port forwarding settings.

Step 2. Apply Dynamic DNS Service from a ISP
  1. Select a dyanmic DNS service ISP, e.g.
  2. Apply an account and apply for a second level domain, e.g. "". this is normally free.
  3. Download & install their auto-update client, run it on your server to bind your server with
Whenever your server's IP address changes or not, now your server is available for Internet visit via "". Because the auto-update client will auto bind your changed server's IP address with your just applied domain

Step 3. On domain control panel, you need to do:
  1. Login your ISP domain control panel (where you applied your domain "").
  2. Create a "MX" record with value of "".
Different ISPs have different domain control panels and mostly them varies significantly. If you are not familiar with this, you can ask your ISP for help, or mail us your domain name, server' Internet IP address, login account/password so that we can configure MX for you.

After domain MX configure ready, your mail server is ready for Internet mail service. Now you could click "Diagnose" toolbar button to run diagnosise wizard for your server in AA Mail Server. Your SMTP server and POP3 server are "" (or you can use directly). Webmail address will be as default.

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