We have 1 forest, A root domain (2008 R2) with exchange 2010, and a second domain (2003) for a branch office. All users in both domains use the same exchange server from the root domain. We would like to consolidate the domains and mover the branch accounts into the root domain. I guess I can use ADMT for that. What happens with the mailboxes? Does exchange recognize that the accounts have been move and connect normally, or do they also need to be edited?Mike Pietrorazio

First, you should move the user accounts via ADMT to the root domain. Then, you should move the mailbox from Exchange 2003 to Exchange 2010. For detail information, please refer to the following article: http://technet.microsoft.com/en-us/library/dd638187.aspx Thanks. Novak Wu TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com 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 Here are some additional links http://blogs.technet.com/b/exchange/archive/2010/08/10/3410619.aspx http://www.thegenerationv.com/2010/03/cross-forest-migration-with-exchange_23.html http://www.testlabs.se/blog/2010/05/24/cross-forest-migration-in-lab/ Jonas Andersson | Microsoft Community Contributor Award 2011 | MCITP: EMA 2007/2010 | Blog: http://www.testlabs.se/blog | Follow me on twitter: jonand82

First, you should move the user accounts via ADMT to the root domain. Then, you should move the mailbox from Exchange 2003 to Exchange 2010. For detail information, please refer to the following article: http://technet.microsoft.com/en-us/library/dd638187.aspx Thanks. Novak Wu TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com 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. There is no exchange 2003. As originally stated, everyone, from both domains are using the same Exchange 2010 server in the root domain.Mike Pietrorazio

Hi Here are some additional links http://blogs.technet.com/b/exchange/archive/2010/08/10/3410619.aspx http://www.thegenerationv.com/2010/03/cross-forest-migration-with-exchange_23.html http://www.testlabs.se/blog/2010/05/24/cross-forest-migration-in-lab/ Jonas Andersson | Microsoft Community Contributor Award 2011 | MCITP: EMA 2007/2010 | Blog: http://www.testlabs.se/blog | Follow me on twitter: jonand82 Thanks for the reply, but this is not a cross-forest migration. As stated above, both domains are in the same forest.Mike Pietrorazio

First, you should move the user accounts via ADMT to the root domain. Then, you should move the mailbox from Exchange 2003 to Exchange 2010. For detail information, please refer to the following article: http://technet.microsoft.com/en-us/library/dd638187.aspx Thanks. Novak Wu TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com 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. There is no exchange 2003. As originally stated, everyone, from both domains are using the same Exchange 2010 server in the root domain. Mike Pietrorazio Then use ADMT for migrating the account and then setup an Exchange 2010 in root domain and move the mailboxes from subdomain to the rootdomain? I missed your first info Jonas Andersson | Microsoft Community Contributor Award 2011 | MCITP: EMA 2007/2010 | Blog: http://www.testlabs.se/blog | Follow me on twitter: jonand82

I think we're getting closer. There is only one exchange server. It is in the root domain. All users (From both domains) are currently using this server. Are you saying I need to move the mailboxes from one domain to another within the same exchange server? If so, how do you do that?Mike Pietrorazio

I’m sorry for misunderstanding in your first post. I understand that you would like to move the user account via ADMT to root domain and verify whether there is any specific configuration about the mailbox. First, I would like to confirm the relationship between the two domains, are they root domain and child domain or just two trusted domains? Based on my research, you just need move the account to the root domain without any configuration on the mailbox if the mailbox is not a link mailbox. To verify the result, you can create a test account in the second domain and build its mailbox on Exchange 2010. Then, please log on the new test mailbox on Windows to send some test messages. At last, move the test account to root domain and check whether the mailbox can be logged normally. Thanks. Novak Wu TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com 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.

Thanks. You have answered my question. And yes, it is 2 trusted domains (not root/child). I planned on testing the way you have indicated anyway. I'll post the results of my test.Mike Pietrorazio

I used a test account for a trial migration. Exchange didn't seem to care that the user had switched domains. That was easy.Mike Pietrorazio