<?php
// Import PHPMailer classes into the global namespace
// These must be at the top of your script, not inside a function
use PHPMailerPHPMailerPHPMailer;
use PHPMailerPHPMailerException;

//Load Composer's autoloader
require 'vendor/autoload.php';

$mail = new PHPMailer(true);                                           // Passing `true` enables exceptions
try {
    //Server settings
    $mail->SMTPDebug = 2;                                              // Enable verbose debug output
    $mail->isSMTP();                                                   // Set mailer to use SMTP
    $mail->Host = 'smtp.aol.com';                                      // Specify main and backup SMTP servers
    $mail->SMTPAuth = true;                                            // Enable SMTP authentication
    $mail->Username = 'xxxxxxxxxxxxxxxxxxx@aol.com';                        // SMTP username
    $mail->Password = 'yyyyyyyyyyyyyyyyyyyyyy';                                     // SMTP password
    $mail->SMTPSecure = 'ssl';                                         // Enable TLS encryption, `ssl` also accepted
    $mail->Port = 465;                                                 // TCP port to connect to

    //Recipients
    $mail->setFrom('xxxxxxxxxxxxxxxxxxx@aol.com', 'Barry AOL');
    $mail->addAddress('xxxxxxxxxxxxxxxxxxx@gmail.com', 'Barry gmail');      // Add a recipient
    //Content
    $mail->isHTML(true);                                               // Set email format to HTML
    $mail->Subject = 'Here is the subject - sent from AOL.com ';
    $mail->Body    = 'This is the HTML message body <b>in bold!</b> - sent from AOL.com ';
    $mail->AltBody = 'This is the body in plain text for non-HTML mail clients - sent from AOL.com ';

    $mail->send();
    echo 'Message has been sent from AOL.com ';
} catch (Exception $e) {
    echo 'Message could not be sent. Mailer Error: ', $mail->ErrorInfo;
}

2018-04-22 21:44:56 SERVER -> CLIENT: 521 5.2.1 : AOL will not accept delivery of this message.
2018-04-22 21:44:56 SMTP ERROR: DATA END command failed: 521 5.2.1 : AOL will not accept delivery of this message.
SMTP Error: data not accepted.
Message could not be sent. Mailer Error: SMTP Error: data not accepted.SMTP server error: DATA END command failed Detail: : AOL will not accept delivery of this message. SMTP code: 521 Additional SMTP info: 5.2.12018-04-22 21:44:56 CLIENT -> SERVER: QUIT
2018-04-22 21:44:56 SERVER -> CLIENT:
2018-04-22 21:44:56 SMTP ERROR: QUIT command failed: