I am investigating if Exchange 2010 can service two separate Active Directory domains. There will be cross domain trusts setup however I can't seem to find any diffinitive answer if this configuration is supported. Can anyone point me in the right direction. Thanks GarthGarth Kirkwood Senior Systems Administrator Stalient Systems

Didn't quite understand what you meant by separate Active Directory domains. I assume that you want to have 1 Exchange 2010 Server deployed for 2 AD Domains with Trust between both the Forests. In this case you can go for Resource Forest for one Ad Domain(with Linked Mailboxes) and for 1 Active Directory domain (on which the server is installed) will be ON-Premise Exchange Server. If you want If you also want to segregate GAL (Address Book) then you would have to implement the Address Book Policies which is possible with Exchange 2010 SP2 Only. Please elaborate your question as it is little unclear regarding to what we are trying to achieve. Exchangeexperts.in ~ ( Exchange | 2003/2007/2010/E15(2013)) ~Mark this if Helpful~ This Information is provided "AS IS" and confers no Rights!!

M.P.K. This is pretty much what we want, Exchange is already set up with one of the AD domains and we have to migrate the other domain off SBS 2003 to straight Win2k8. Are you able to point me in the direction of some doco that may explain this configuration you talk about in more detail. ThanksGarth Kirkwood Senior Systems Administrator Stalient Systems

First, we need to make sure that you are getting your terminology correct. Exchange is installed as a forest resource and easily services all of the domains in the forest. I believe that in your case, your domains are in different forests, since you are indicating that you are setting up trusts (trusts are inherent within a forest) Exchange 2010 supports linked mailboxes. A linked mailbox is one in which Exchange is in domain B and the user's primary account in is domain A. Basically, from the source domain account, you create an account in the target domain and link it together. The mailbox is then attached to the account in the target domain, but linked to the source domain. The user still logs onto the source domain and uses it's password.Ed

I am still not able to understand your infrastructure. have you already got a trust set-up between your SBS & NON-SBS domains ? If you are looking for an option of creating trust between a SBS and a non-sbs domain then, I'm afraid if trust is possible between a SBS domain and a NON-SBS Domain. But there is a workaround though. Check for the Section with the text "Are there any design constraints with SBS". Windows Small Business Server 2008 Technical FAQ SBS 2003 to SBS 2008 Migration to a Different Domain Name the work around that i was talking about is:- - Install a Windows DC in the SBS domain & Install an Exchange Server on that machine. - Move the mailboxes to the new Exchange server on the new DC. - After the mailboxes are all moved, run dcpromo down the SBS DC and uninstall the old Exchange server gracefully. - Then establish the trust with the new domain, use ADMT to move accounts with SID history, and we can go ahead and move mailboxes or enable the linked mailboxes if you want to keep your topology as Resource Forest. Exchangeexperts.in ~ ( Exchange | 2003/2007/2010/E15(2013)) ~Mark this if Helpful~ This Information is provided "AS IS" and confers no Rights!!

Hi, Yes. Please refer to Resource and User forests Topology below: http://technet.microsoft.com/en-us/library/aa998031.aspx Thanks, Simon Wu Exchange Forum Support Please remember to mark the replies as answers if they help and unmark them if they provide no help. If you have feedback for TechNet Subscriber Support, contact tnmff@microsoft.com