# PowerShell script to list senders of emails from an on-premise Exchange server for the current day.

# Set the start and end times for today
$today = Get-Date -Hour 0 -Minute 0 -Second 0
$tomorrow = (Get-Date).AddDays(1).Date

Write-Host "Searching for emails sent between $($today) and $($tomorrow)..."

try {
    # Get message tracking logs for sent emails within today's date range
    # Filtering by EventID 'SEND' focuses on emails leaving the server or being sent internally.
    # Adjust -ResultSize as needed; 'Unlimited' retrieves all, but can be slow for large environments.
    $sentEmails = Get-MessageTrackingLog -Start $today -End $tomorrow -EventId "SEND" -ResultSize Unlimited |
                  Select-Object -ExpandProperty Sender |
                  Sort-Object -Unique

    if ($sentEmails) {
        Write-Host "`nSenders of emails today:`n"
        $sentEmails | ForEach-Object {
            Write-Host $_
        }
        Write-Host "`nTotal unique senders: $($sentEmails.Count)"
    } else {
        Write-Host "`nNo emails sent today found."
    }
}
catch {
    Write-Error "An error occurred while retrieving message tracking logs: $($_.Exception.Message)"
    Write-Error "Please ensure you have the necessary Exchange management tools installed and are running the script with appropriate permissions."
}