When deleting a mailbox from the Exchange server, the user's mailbox and its AD account will be deleted:
This deleted mailbox will become "disable" status which hosted on database(Please note: This disabled mailbox is only kept in the database for 30 days by default, if you cannot find this mailbox with command below, you will cannot recover this mailbox):
If you want to recover this mailbox, you need to recreate this an AD user first, then use command below to reconnect this mailbox to this AD account:
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