Move the mail to another organization.

Question

Hello. There are two forests with an Exchange server.

We want to move the second organization's mailboxes to the first.

I found the instructions. https://www.exchangerecover.com/blog/2013/cross-forest-migration-exchange-2013.html

How to do it right ?

1. Add a new domain to my organization ? (New-AcceptedDomain)
2. Move the boxes.
3. Switch the MX record.
4. now I can delete the second organization ?

Or maybe in my mail domain I can make an internal forwarding connector and transfer one box at a time ? For example when an email comes to my Exchange server, it will see the new box for this domain and receive the email, if not, redirect to the mail server of the second organization ? In this way I can migrate mailboxes slowly ?

Answer 1

@Андрей Михалевский

For cross-forest migration, you need have Exchange server in both forest.

You need to create forest trust before migration, then prepare mailbox for cross-forest migration. You could follow this blog to cross forest migration.
Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.

About migrate mailbox, you could create migration mailbox one by one, you can also migration a part of mailboxes in a batch.

If you want to use old forest domain name in new forest, you need to remove the forest trust after migration, then add old domain as accepted domain in new forest. Then change MX record to the new forest.

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