chagne of domain from .ae to .com in Exchange

If you are using SBS 2003 it is properly configured using .ae for local and .com for external. In server management run the internet configuration wizard. When you get to the email setup put your external domain name ie domain.com. After the wizard completes Exchange will be setup to send and receive email for that domain. If you want to download POP3 account to Exchange mailboxes use the pop3 connector. Enter the account information for each pop account and the exchange mailbox you want it routed to. You can use this in addition to the Exchange setup.

my problem is following. the IP no which is given is not my IP.
trading@naintnl.com on 07-Feb-08 11:07 AM
            There was a SMTP communication problem with the recipient's email server.  Please contact your system administrator.
            <mailserver.sharifmetals.ae #5.5.0 smtp;550-5.7.1 [83.110.145.60] The IP you're using to send email is not authorized >

From this your post it looks like your IP has been blocked as spam. Please go to www.dnsstuff.com and do a spam database lookup on your domain. If you are blocked it will show in red. Are you using a dynamic IP or static. Most mail servers these days will block any mail comming from dynamic IP ranges. I have seen instances where the ISP give you a static IP from a dynamic range and mail is blocked. If that is not your IP, how many MX records do you have? Please use www.dnsreport.com and do a DNS report to help troubleshoot your DNS records.

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