MFAReportMailboxes.ps1

# MFAReportMailboxes.ps1
# List mailboxes and the last time MFA processed each mailbox
$Mbx = Get-Mailbox -RecipientTypeDetails UserMailbox -ResultSize Unlimited
$Report = @()
ForEach ($M in $Mbx) {
   $LastProcessed = $Null
   Write-Host "Processing" $M.DisplayName
   $Log = Export-MailboxDiagnosticLogs -Identity $M.Alias -ExtendedProperties
   $xml = [xml]($Log.MailboxLog)  
   $LastProcessed = ($xml.Properties.MailboxTable.Property | ? {$_.Name -like "*ELCLastSuccessTimestamp*"}).Value   
   $ItemsDeleted  = $xml.Properties.MailboxTable.Property | ? {$_.Name -like "*ElcLastRunDeletedFromRootItemCount*"}
   If ($LastProcessed -eq $Null) {
      $LastProcessed = "Not processed"}
   $ReportLine = [PSCustomObject][Ordered]@{
           User          = $M.DisplayName
           LastProcessed = $LastProcessed
           ItemsDeleted  = $ItemsDeleted.Value}      
    $Report += $ReportLine
  }
$Report | Select User, LastProcessed, ItemsDeleted