We've merged with another company, and part of our revamp is to move to a new hosting location, and new servers.
The company currently has an Exchange 2007 server/s, with about 200 mailboxes, for say, abc.com (i.e. users' addresses are grimstoner@abc.com). These Exchange machines are part of the AD domain, abc.local.
We installed new servers, and to avoid inheriting years of bad admin, we created a new AD domain called, say, def.local, in which we deployed our new Exchange 2013 servers (2 x Hubs, 2 x Storage).
There exists a two-way trust between abc.local and def.local. I'm able to assign permissions for def.local resources to abc.local users, and vice versa.
Is it possible to move the mailboxes between these two setups? We still want to keep the old email domain, abc.com, and, the users should still be able to access this mailbox with their abc.local AD account.
I've seen http://technet.microsoft.com/en-us/library/ee633491(v=exchg.150).aspx, but in that case the user would have to login to their mailbox using an account created for them in the def.local AD domain.
Best Answer
We have recently had the same problem. We found out that you cannot migrate the mailboxes in Exchange 2007 to 2013. Microsoft states that they are going to come out with a tool that allows you to do so. BUT you can migrate them to Exchange 2010 then to 2013. Its completely up to you if you want to wait for the tool that can do it for you. Or you can migrate from 2007 to 2010 then to 2013. Yeah we were also kind of upset when we found this news out. :P