Hi All,My company only got one AD domain (domain.com) therefore all of the email address is in this format username@domain.com same as our website domain.com.at the moment we're hosting another service mydomain.com and I'm just wondering if within the same AD domain and Exchange Server I could make the email address for certain people becomes username@mydomain.com and username@domain.comis that possible using one single AD ?i know that if it's DNS name, i can just easily create a new mycomain.com forward lookup zone to point to the same servers.I'm looking forward for your reply.Thanks/* Support Engineer */

Hey Albert,Are you using Exchange 2007? If so, check out below similar thread...http://social.technet.microsoft.com/Forums/en-US/exchangesvrdeploy/thread/06c722c0-5040-488d-bbed-6a77ec9af54f/Amit Tank | MVP - Exchange | MCITP:EMA MCSA:M | http://ExchangeShare.WordPress.com

Amit,yes it worked here's what I've done:1. create AD DNS Zone of mydomain.com in my DNS mgmt. console2. create mx record which points to the Exchange Server in the domain.com3. create in EMC for AcceptedDomains | mydomain.com as Authoritative.4. go to the desired mailbox and then uncheck the email address policy rule and make username@mydomain.comCheers,Albert /* Support Engineer */