Exchange 2016/2019 – Find those Pesky System Mailboxes

Every upgrade, every time, there seems to be one forgotten mailbox that wasn’t moved and we get the infamous pop-up like so:

So what to do? There are so many possible types of mailboxes that could be causing us issues:

• Arbitration
• AuditLog
• AuxAuditLog
• Archive
• Monitoring
• RemoveArchive
• Migration

How can discover be handled programmatically? Well, we can build a PowerShell script that can take a look at a particular server and let you know what mailboxes exist that are impeding its removal. The script below is a bit over done, but it provides a good visual on what mailboxes are on that server:

Code

# Script to move all system mailboxes and remove excess HealthMailboxes
CLS
Write-host '######################################' -ForegroundColor Green
Write-host '# ' -ForegroundColor Green -NoNewLine
Write-host 'System / Non-Primary Mailbox Check' -ForegroundColor White -NoNewLine
Write-host ' #' -ForegroundColor Green
Write-host '######################################' -ForegroundColor Green
Write-Host ' '
Write-Host ' '

# Pause for a sec #
start-Sleep 4

## Script Body ##

Write-host 'Which Exchange Server do you want to check' -ForegroundColor Yellow -NoNewLine
Write-host " for mailboxes? ('d' - default or enter name)  " -ForegroundColor Yellow -NoNewLine
$Answer = Read-host

If ($Answer -eq 'd') {
	# Server Name Check
	$ExchangeServer = $Env:ComputerName
	$AllServers = (Get-ExchangeServer).name
	If ($AllServers -Contains $ExchangeServer){
		$ExServer = $ExchangeServer
	} Else {
		Write-host "Error - this is not an Exchange Server!" -ForegroundColor Red
	}
} Else {

	
	# Server Name Check
	$AllServers = (Get-ExchangeServer).name
	If ($AllServers -Contains $Answer){
		$ExServer = $Answer
	} Else {
		Write-host "Error - this is not an Exchange Server!" -ForegroundColor Red
	}
}

Write-host "  "
Write-host "  "
Write-host "Checking the Exchange Server $ExServer for mailboxes now...." -ForegroundColor Yellow
Write-host "  "

# Mailbox Check
$ArbitrationMailboxes = Get-Mailbox -Arbitration -Server $ExServer | Select-Object Name,ServerName
$ArchiveMailboxes = Get-Mailbox -Archive -Server $ExServer | Select-Object Name,ServerName
$AuditLogMailboxes = Get-Mailbox -AuditLog -Server $ExServer | Select-Object Name,ServerName
$AuxAuditLogMailboxes = Get-Mailbox -AuxAuditLog -Server $ExServer | Select-Object Name,ServerName
$MigrationMailboxes = Get-Mailbox -Migration -Server $ExServer | Select-Object Name,ServerName
$MonitoringMailboxes = Get-Mailbox -Monitoring -Server $ExServer | Select-Object Name,ServerName
$PublicFolderMailboxes = Get-Mailbox -PublicFolder -Server $ExServer | Select-Object Name,ServerName

# ARBITRATION MAILBOX CHECK:
# --------------------------
If ($Null -ne $ArbitrationMailboxes) {
    
    Write-Host "Arbitration " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found:" -ForegroundColor White
    Write-host "------------------------------" -ForegroundColor White
    Write-host "Name,Server,Type"
    Foreach($Mailbox in $ArbitrationMailboxes) {
        $Server = $Mailbox.ServerName
        $Mbx = $Mailbox.Name
        write-host "$Mbx,$Server,Arbitration"
    }
} Else {

    Write-host "No " -ForegroundColor White -NoNewLine
    Write-Host "Arbitration " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found" -ForegroundColor White
}

# Archive MAILBOX CHECK:
# --------------------------
If ($Null -ne $ArchiveMailboxes) {
    Write-Host ""
    Write-Host "Archive " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found:" -ForegroundColor White
    Write-host "------------------------------" -ForegroundColor White
    Write-host "Name,Server,Type"
    Foreach($Mailbox in $ArchiveMailboxes) {
        $Server = $Mailbox.ServerName
        $Mbx = $Mailbox.Name
        write-host "$Mbx,$Server,Archive"
    }
	Write-Host ""
} Else {

    Write-host "No " -ForegroundColor White -NoNewLine
    Write-Host "Archive " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found" -ForegroundColor White
}

# AuditLog MAILBOX CHECK:
# --------------------------
If ($Null -ne $AuditLogMailboxes) {
    Write-Host ""
    Write-Host "AuditLog " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found:" -ForegroundColor White
    Write-host "------------------------------" -ForegroundColor White
    Write-host "Name,Server,Type"
    Foreach($Mailbox in $AuditLogMailboxes) {
        $Server = $Mailbox.ServerName
        $Mbx = $Mailbox.Name
        write-host "$Mbx,$Server,AuditLog"
    }
	Write-Host ""
} Else {

    Write-host "No " -ForegroundColor White -NoNewLine
    Write-Host "AuditLog " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found" -ForegroundColor White
}



# AuxAuditLog MAILBOX CHECK:
# --------------------------
If ($Null -ne $AuxAuditLogMailboxes) {
    Write-Host ""
    Write-Host "AuxAuditLog " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found:" -ForegroundColor White
    Write-host "------------------------------" -ForegroundColor White
    Write-host "Name,Server,Type"
    Foreach($Mailbox in $AuxAuditLogMailboxes) {
        $Server = $Mailbox.ServerName
        $Mbx = $Mailbox.Name
        write-host "$Mbx,$Server,AuxAuditLog"
    }	Write-Host ""
} Else {

    Write-host "No " -ForegroundColor White -NoNewLine
    Write-Host "AuxAuditLog " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found" -ForegroundColor White
}

# Migration MAILBOX CHECK:
# --------------------------
If ($Null -ne $MigrationMailboxes) {
    Write-Host ""
    Write-Host "Migration " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found:" -ForegroundColor White
    Write-host "------------------------------" -ForegroundColor White
    Write-host "Name,Server,Type"
    Foreach($Mailbox in $MigrationMailboxes) {
        $Server = $Mailbox.ServerName
        $Mbx = $Mailbox.Name
        write-host "$Mbx,$Server,Migration"
    }
	Write-Host ""
} Else {

    Write-host "No " -ForegroundColor White -NoNewLine
    Write-Host "Migration " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found" -ForegroundColor White
}

# Monitoring MAILBOX CHECK:
# --------------------------
If ($Null -ne $MonitoringMailboxes) {
    Write-Host ""
    Write-Host "Monitoring " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found:" -ForegroundColor White
    Write-host "------------------------------" -ForegroundColor White
    Write-host "Name,Server,Type"
    Foreach($Mailbox in $MonitoringMailboxes) {
        $Server = $Mailbox.ServerName
        $Mbx = $Mailbox.Name
        write-host "$Mbx,$Server,Monitoring"
    }
	Write-Host ""
} Else {

    Write-host "No " -ForegroundColor White -NoNewLine
    Write-Host "Monitoring " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found" -ForegroundColor White
}

# PublicFolder MAILBOX CHECK:
# --------------------------
If ($Null -ne $PublicFolderMailboxes) {
    Write-Host ""
    Write-Host "PublicFolder " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found:" -ForegroundColor White
    Write-host "------------------------------" -ForegroundColor White
    Write-host "Name,Server,Type"
    Foreach($Mailbox in $PublicFolderMailboxes) {
        $Server = $Mailbox.ServerName
        $Mbx = $Mailbox.Name
        write-host "$Mbx,$Server,PublicFolder"
    }
	Write-Host ""
} Else {

    Write-host "No " -ForegroundColor White -NoNewLine
    Write-Host "PublicFolder " -ForegroundColor Green -NoNewLine
    Write-host "mailboxes found" -ForegroundColor White
}

Sample Run Through

Here is a sample run through for discovering these mailboxes on either Exchange 2016 or Exchange 2019.



Conclusion</strong

Hope you find this script useful in your migrations / maintenance of Exchange Server 2016/2019.