How can I send an email via PHPMAILER without SSL - port 25?

Question

I want to send an email without SSL using PHPMailer. I have enabled the debug mode so that I can check the details in the logs.

    $mail = new PHPMailer\PHPMailer\PHPMailer();
    $mail->IsSMTP(true); // enable SMTP
    $mail->SMTPDebug = 1; // debugging: 1 = errors and messages, 2 = messages only
    $mail->SMTPAuth = true; // authentication enabled
    $mail->SMTPSecure = false; // secure transfer enabled REQUIRED for Gmail
    $mail->Host = "mail.company.co.uk";
    $mail->Port = 25; // or 587
    $mail->IsHTML(true);
    $mail->Username = "[email protected]";
    $mail->Password = "password_of_username";
    $mail->SetFrom($email,$name);
    $mail->Subject = $subject;
    $mail->Body = $message;
    $mail->AddAddress($to);

This is giving an exception:

2018-09-28 10:04:27 CLIENT -&gt; SERVER: EHLO localhost<br>
2018-09-28 10:04:27 CLIENT -&gt; SERVER: STARTTLS<br>
SMTP Error: Could not connect to SMTP host.<br>
2018-09-28 10:04:28 CLIENT -&gt; SERVER: QUIT<br>
2018-09-28 10:04:28 <br>
SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting<br>
Mailer Error: SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting

Answer 1

You've based your code on an old example, which doesn't help. You can't see what's going on because you've only used 1 for SMTPDebug; set it to 2.

Your mail server is advertising that it supports STARTTLS on port 25, so PHPMailer is using it automatically. You can disable encryption entirely by doing this:

$mail->SMTPAutoTLS = false;
$mail->SMTPSecure = false;

However, I'd recommend not doing this; fix your TLS config instead. You probably need to update your local CA certificate bundle - see the troubleshooting guide for more details.