How can access to mail server log files help troubleshoot issues with PHP email delivery?

Access to mail server log files can help troubleshoot PHP email delivery issues by providing detailed information on the status of email transactions, such as whether the email was successfully sent or if there were any errors encountered during the process. By reviewing these log files, developers can identify the root cause of the problem and make necessary adjustments to their PHP email delivery code.

// Example PHP code snippet to log email delivery status
// Assuming the mail server log file is located at /var/log/mail.log

$to = "recipient@example.com";
$subject = "Test Email";
$message = "This is a test email.";

if (mail($to, $subject, $message)) {
    error_log("Email sent successfully", 3, "/var/log/mail.log");
} else {
    error_log("Failed to send email", 3, "/var/log/mail.log");
}