Hi @DG1212-6330
Following these steps, I shouldn't have clients connect to Exchange 2019 before step 7, correct?
Theoretically this can work, but I’ve also seen cases that clients could still connect to the new server unexpectedly. So to be on a safe side, it is recommended to put the Exchange Server 2019 in maintenance mode before the servers are fully configured.
Please can refer to: Put Exchange Server in maintenance mode
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