in my company i have alocal mail (not exchange) and external mail hosted at ISP, i want to install exchange server 2007 as alocal mail (ex: abc.local) inside my company then i want to configure it to receive the external mail also In other words i want to install one exchange server and recieve emails from two domains one local and another external (that hosted at isp) , what the microsoft recommended setps for this case.

http://technet.microsoft.com/en-us/library/aa996314.aspx

also a video if you would like. http://technet.microsoft.com/en-us/exchange/cc950455.aspx

Hi, Lmurthy’s idea is right, but sorry that the first link he gave is for Exchange 2010. In Exchange 2007, it can achieved by configuring authoritative domains. For more information, you can refer to the article How to Configure Exchange 2007 to Accept E-Mail for More Than One Authoritative Domain. Hope this helps. Thanks Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hi Ahmed, I hope you are familiar with exchange server 2007 installation. Whenever you install exchange server 2007 on abc.local domain by default that exchange server will be responsible for sending and receiving mails for abc.local domain. If you wanted to send and receiving mails for external domain that is hosted on your ISP you have to do the following steps: You have to configure one authoritative domain on your exchange server 2007 for your external domain. create the same number of mailboxes on your exchange server (the email address should match the external address) Create a new mx record by cordinating with your ISP and point the same to your internal exchange server (I hope you have free public ip address for hosting your mail server) and do the required change on your network (NAT). Thnaks, Santhosh Santhosh Sivaraman MCITP: Microsoft Exchange Server 2007/2010 | MCSE/MCSA

Thanks all Dear Santhosh, the mail boxes that i will created must be the same mail boxes at ISP & could you more explain about mx record , please? Thanks,

Hi, The mailboxes that you will create don’t need to be the same mailboxes at ISP. But the external Domain Name System (DNS) servers for your domain must have mail exchanger (MX) resource records pointing to your mail servers, or, if you are using an Internet service provider (ISP) or an external system, this external system must have an MX record for your domain and a mechanism to forward mail to your Exchange servers. For more information, you can refer to the question '7. What are the minimum requirements for receiving Internet mail flow in Exchange server 2003? ' Hope this helps. ThanksPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Thanks all Dear Santhosh, the mail boxes that i will created must be the same mail boxes at ISP & could you more explain about mx record , please? Thanks, If you are not creating the current ISP's mailboxes on your exchange server after changing the MX records, whenever other outside users send mails to your organisation it will get bounced (I guess you will be cancelling your ISP's mailbox subscription) back. A mail exchanger record (MX record) is a type of resource record in the Domain Name System that specifies a mail server responsible for accepting email messages on behalf of a recipient's domain. If you have access to your public dns control panel then you can do it yourself. Otherwise you have to cordinate with your ISP. Santhosh Sivaraman MCITP: Microsoft Exchange Server 2007/2010 | MCSE/MCSA