Make a disconnected mailbox visible

When you delete a mailbox or an Active Directory account, the soft-deleted or disconnected mailbox won’t immediately appear in the list of disconnected mailboxes. The mailbox status is updated as part of a mailbox store maintenance task.

When you query a mailbox database for disconnected mailboxes, you will find a mailbox having the DisconnectReason and DisconnectDate attributes empty.

# Query the mailbox using the original user display name 
Get-MailboxDatabase | Get-MailboxStatistics | Where { $_.DisplayName -eq "LASTNAME, FIRSTNAME" } | fl DisconnectReason,DisconnectDate,MailboxGuid,Database 

# Use wildcards if the correct display name is unknown 
Get-MailboxDatabase | Get-MailboxStatistics | Where { $_.DisplayName -like "*LASTNAME*" } | fl DisconnectReason,DisconnectDate,MailboxGuid,Database 

DisconnectReason :
DisconnectDate   :
MailboxGuid      : a04a8aab-c360-406b-a194-8c290d56668b
Database         : MBXDB34

You can find disconnected mailboxes by

• DisplayName
• MailboxGuid
• LegacyExchangeDN

The following PowerShell cmdlet updates the mailbox state of a single mailbox using the MailboxGuid as an identifier.

Update-StoreMailboxState -Database MBXDB34 -Identity a04a8aab-c360-406b-a194-8c290d56668b

After updating the mailbox state, the DisconnectReason and DisconnectDate attributes are correctly set.

Get-MailboxDatabase | Get-MailboxStatistics | Where { $_.DisplayName -eq "LASTNAME, FIRSTNAME" } | fl DisconnectReason,DisconnectDate,MailboxGuid,Database 

DisconnectReason : 
DisabledDisconnectDate   : 01.01.2017 15:02:59
MailboxGuid      : a04a8aab-c360-406b-a194-8c290d56668b
Database         : MBXDB34

The disconnected mailbox is now visible in Exchange Administrative Center (EAC) and can be reconnected using EAC or Exchange Management Shell.

By default, a disconnected mailbox is supposed to be connected to its original account having a matching LegacyExchangeDN attribute. Connecting the mailbox to a different Active Directory account requires using the AllowLegacyDNMismatch parameter.

# Connect a mailbox to the original AD account having a matching LegacyExchangeDN

Connect-Mailbox -Database MBXDB34 -Identity "Doe, John"

# Connect a mailbox to a different AD account 
Connect-Mailbox -Database MBXDB34 -Identity "Doe, John" -User "Jane Doe" -AllowLegacyDNMismatch

Examples of room and shared mailboxes are described in the Connect-Mailbox documentation.

Links

• Connect-Mailbox