Our firm is acquiring another smaller firm. We are currently running Exchange 2010 and they are running Exchange 2013. We have about 215 users and they have 25. We will be pulling all apps and data into our datacenter and retiring their servers and existing domain leaving only a single domain controller and print server from our domain. I need to export these mailboxes from the Exchange 2013 server over to our Exchange 2010 org. They will not co-exist in the same forest. In previous versions I have used Exmerge to save the mailboxes as pst files and then I imported these pst files into the other server.
I'm sure this is a PowerShell command and I think it's probably the MailboxExportRequest command. I think this will export a mailbox to a pst. How do I then import this into the 2010 Exchange server? Do I need to simply have the account and empty mailboxes created and then run a similar command to pull this pst data into the associated mailbox on the 2010 server? If so, will this copy over everything in the mailbox? calendar, contacts, etc.