I have install a new Exchange 2016 to migrate from Exchange 2010 SP3. I have a problem is that when I migrate the Mailbox from Exchange 2010 DB to Exhange 2010 DB, the Outlook will be disconnected and the customer cann't use Outlook.
When I migaret back the mailbox to the Exchange 2010, the Outllook will connect and the customer can use it to send and receive email.
Thanks
The 2016 acts as proxy for the 2010