$ExportPath = "" #Specify the export path as UNC path!
$Mailboxes = Get-Mailbox -ResultSize Unlimited
$TotalMailboxes = $Mailboxes.Count
$CurrentMailbox = 0

foreach ($Mailbox in $Mailboxes) {
    $CurrentMailbox++

    # Start Export Request
    New-MailboxExportRequest -Mailbox $Mailbox.Identity -FilePath "$ExportPath\$($Mailbox.Alias).pst"

    Write-Host "Export started for: $($Mailbox.Alias). Waiting for completion..."

    do {
        Start-Sleep -Seconds 5  # Wait before checking again
        
        # Check if the mailbox export is still in progress
        $ExportRequest = Get-MailboxExportRequest -Mailbox $Mailbox.Identity | Where-Object { $_.Status -ne "Completed" }
        $ExportStats = Get-MailboxExportRequestStatistics -Mailbox $Mailbox.Identity -ErrorAction SilentlyContinue

        # Get completion percentage of the current mailbox export
        $MailboxPercentComplete = if ($ExportStats) { $ExportStats.PercentComplete } else { 0 }

        # Calculate overall progress
        $OverallPercentComplete = [math]::Round((($CurrentMailbox - 1 + ($MailboxPercentComplete / 100)) / $TotalMailboxes) * 100, 2)

        # Display Progress Bar for Overall Process
        Write-Progress -Activity "Exporting Mailboxes" `
                       -Status "Processing: $($Mailbox.Alias) ($MailboxPercentComplete% complete)" `
                       -PercentComplete $OverallPercentComplete
    } while ($ExportRequest)

    Write-Host "Export completed for: $($Mailbox.Alias)"
}

Write-Host "All mailbox exports completed!"