Hello, I have two companies (A & B), both with their own server running SBS2003, both with their own domain names (domainA.com & domainB.com). I need some of the users in domain B to have a primary email address of user@domainA.com. Currently I am managing to do this by creating a user (UserX) on both servers with email addresses of UserX@domainA.com and UserX@domainB.com respectively, then creating a contact on server A to point to UserX on server B and finally configuring the account for UserX on server A to forward all emails to UserX@domainB.com. This works, but is messy and means I have lots of unnecessary users setup on serverA. As an alternative, I have tried working through article 321721 - How to share an SMTP address space in Exchange Server 2003 (Method 1). This seems to work but with one major issue - users on server B cannot send emails to users on Server A. I think this is because server B is configured as authoritative for domainA.com (so that it will generate NDR's) and hence when a user on that server attempts to send to a user on Server A, ServerB cannot resolve the email address and generates an NDR. If I try configuring server B as non-authoritative and setting up a connector to server A for domain A, then, unsuprisingly I end up with emails getting bounced between the two servers! The article does not discuss how to configure the foreign messaging system (Server B in my case) so I am guessing as to what to do. Does anyone know what I am doing wrong and how to configure server B so the address space sharing works? Thanks Steve Everington

Hi, This is the Exchange 2003 related to SBS, please post it to the below link to get the support. http://social.technet.microsoft.com/Forums/en-US/smallbusinessserver/threads Thanks Allen