Hello,

I hope somebody can help me with my Issue.

First i'll give you a short Information about the Migration Scenario..

-Installation new domain

-Installation Exchange 2013

- we migrated Users with admt to a new domain

- The users are present to the Exchange so i attached the mailboxes to a MailboxDatabase

- Everything seems to be fine, we can Access the Mailbox but when  I configure the Mailbox and open the "Mailbox Feature" i get the following errormessage:

The Get-MobileDeviceStatistics command that you are trying to run, which is version 15, requires that the target mailbox account is on a Mailbox server that is the same version. The command wasn't able to process your request because the target mailbox account is on a Mailbox server with version 8. Please use this version (Version: 8) of the Get-MobileDeviceStatistics command.

So im confused about that because i can Access the Mailbox without any Issues and want to start to Import the exported PST Files from the old Exchange Server 2007 from the old Domain...

Thanks for any help!

I could resolve the Issue:

1. Disable the Mailbox

2. Create the Mailbox with the User

Now everything is working without any Errormessage in the Options.