Hi all, My organization run one Exchange 2007 server for internal email exchange. Basically it does not exchange mail with any other server. All clients are inside our LAN. Now we need to add a second mailserver running Postfix on an Ubuntu Linux 10.10 server. We need to migrate some user mailboxes to the Postfix server and enable both server to exchange mail each other. The Linux server is integrated to the existing Active Directory domain to enable users to use the same password for both Windows and Linux. Then the Linux host is called mailserver2.mydomain.net where mydomain.net is the Active Directory domain not connected to the internet. Exchange 2007 is mailserver1.matusa.net. Exchange mail users are user1@mydomain.net. Linux mail users are user2@mailserver2.mydomain.net. I already could configure Linux server to relay mail for user1@mydomain.net to the Exchange server. But how can I configure Exchange to relay mail to user2@mailserver2.mydomain.net to the mailserver2.mydomain.net server? Thanks in advance Sammy

Configure Exchange 2010 to Route Messages for a Shared Address Space http://technet.microsoft.com/en-us/library/bb676395.aspx Mike Crowley Check out My Blog!