I am migrating from a legacy POP/IMAP/SMTP mail system that currently owns the namespace for @company.com addresses. I am introducing Exchange 2007 into this environment, and Id like to have Exchange receive all messages for @company.com, and attempt local delivery of those messages. Any addresses that cannot be locally resolved would be forwarded to the legacy mail system.Is this possible? I don't want to have to create contacts for users in the legacy system if I don't have to.

Its the same as a non-authoritative domain. Simply specify the domain as internal relay, and configure a Send Connector to forward mail for that domain to a smart host. See: http://technet.microsoft.com/en-us/library/aa996910.aspx

Hi,Does this not incur an Exchange 2007 CAL for each of the recipient addresses that are relayed? I was looking to do something similar, except use a sendmail/linux system as the smart host, but was told that I'd need a CAL for every email address on the smart host that had passed through the Exchange system.Matt

I am kind of in the same boat, and need to figure out a way to relay the mail as such: We currently, via certs, use outlook to connect to a hosted mail server. they control all spam, mail flow and MX records. We want to move mail in house, but have NO access to the exchange server. What we are thinking of doing is: The domain name at the hoster, is mycompany.com and the new mailserver will be hosting mycompany.com internally instead of at the ISP. The MX record points to smtp.my-hoster.com (as a MX recond in DNS for mycompany.com) What I need to do it, figure out a why that I can redirect mail to my new mycompany.com mail server and if the "test" group or simply the user isnt setup on AD, the mail will fail over to my existing mycompany.com mail server. I thought I would simply be able to do this via MX records, but that simply points it to the right mail server and not so much put them to the correct server. Anybody got a link for me to look this up, I dontneed a how to just a point in the right direction if possible! Thanks so much! ivanmor