Send Remote Emails with PHPMailer

This section provides a tutorial example on how to send remote emails with PHPMailer using STMP protocol.

If you don't have an email server running on your local host, you can use PHPMailer's isSMTP() option to use the SMTP protocol to deliver emails to a remote email server.

Here is a PHP script that delivers emails to a remote email server using the SMTP protocol without the Opportunistic TLS option.

<?php
#  PHPMailer-Send-Email-Remotely.php
#- Copyright 2019 (c) HerongYang.com. All Rights Reserved.

use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\SMTP;
use PHPMailer\PHPMailer\Exception;

$srcDir = "/home/herong/local/php/vendor/phpmailer/phpmailer/src/";
require "$srcDir/PHPMailer.php";
require "$srcDir/SMTP.php";
require "$srcDir/Exception.php";

$mail = new PHPMailer(true);
$mail->SMTPDebug = 4;
$mail->isSMTP();
$mail->SMTPAutoTLS = false; # default is "true"
$mail->Host = "192.168.1.25";

try {
   $mail->setFrom('joe@herongyang.com', 'Joe Doe');
   $mail->addAddress('herong@herongyang.com', 'Herong Yang');
   $mail->Subject = 'PHPMailer Test - Remote Delivery';
   $mail->Body = 'There is a test message from PHPMailer.';
   $mail->send();
} catch (Exception $e) {
   # PHPMailer exceptions
   echo $e->errorMessage();
} catch (\Exception $e) {
   # PHP exceptions
   echo $e->getMessage();
}
?>

Run the above PHP script, you will get the follow debugging messages.

[herong@mail php]$ php PHPMailer-Send-Email-Remotely.php
...	Connection: opening to 192.168.1.25:25, timeout=300, options=array()
...	Connection: opened
...	SMTP INBOUND: "220 mail.herongyang.com ESMTP Postfix"
...	SERVER -> CLIENT: 220 mail.herongyang.com ESMTP Postfix
...	CLIENT -> SERVER: EHLO mail.herongyang.com
...	SMTP INBOUND: "250-mail.herongyang.com"
...	SMTP INBOUND: "250-PIPELINING"
...	SMTP INBOUND: "250-SIZE 5111222333"
...	SMTP INBOUND: "250-VRFY"
...	SMTP INBOUND: "250-ETRN"
...	SMTP INBOUND: "250-STARTTLS"
...	SMTP INBOUND: "250-ENHANCEDSTATUSCODES"
...	SMTP INBOUND: "250-8BITMIME"
...	SMTP INBOUND: "250-DSN"
...	SMTP INBOUND: "250 SMTPUTF8"

...	CLIENT -> SERVER: MAIL FROM:<joe@herongyang.com>
...	SMTP INBOUND: "250 2.1.0 Ok"
...	SERVER -> CLIENT: 250 2.1.0 Ok
...	CLIENT -> SERVER: RCPT TO:<herong@herongyang.com>
...	SMTP INBOUND: "250 2.1.5 Ok"
...	SERVER -> CLIENT: 250 2.1.5 Ok
...	CLIENT -> SERVER: DATA
...	SMTP INBOUND: "354 End data with <CR><LF>.<CR><LF>"
...	SERVER -> CLIENT: 354 End data with <CR><LF>.<CR><LF>
...	CLIENT -> SERVER: Date: Sun, 13 Jun 2021 08:18:02 +0000
...	CLIENT -> SERVER: To: Herong Yang <herong@herongyang.com>
...	CLIENT -> SERVER: From: Joe Doe <joe@herongyang.com>
...	CLIENT -> SERVER: Subject: PHPMailer Test - Remote Delivery
...	CLIENT -> SERVER: Message-ID: <...@mail.herongyang.com>
...	CLIENT -> SERVER: X-Mailer: PHPMailer 6.4.1
...	CLIENT -> SERVER: MIME-Version: 1.0
...	CLIENT -> SERVER: Content-Type: text/plain; charset=iso-8859-1
...	CLIENT -> SERVER:
...	CLIENT -> SERVER: There is a test message from PHPMailer.
...	CLIENT -> SERVER:
...	CLIENT -> SERVER: .
...	SMTP INBOUND: "250 2.0.0 Ok: queued as ..."
...	SERVER -> CLIENT: 250 2.0.0 Ok: queued as ...
...	CLIENT -> SERVER: QUIT
...	SMTP INBOUND: "221 2.0.0 Bye"
...	SERVER -> CLIENT: 221 2.0.0 Bye
...	Connection: closed

Table of Contents

 About This Book

 Introduction and Installation of PHP 7.3

 PHP Script File Syntax

 PHP Data Types and Data Literals

 Variables, References, and Constants

 Expressions, Operations and Type Conversions

 Conditional Statements - "if" and "switch"

 Loop Statements - "while", "for", and "do ... while"

 Function Declaration, Arguments, and Return Values

 Arrays - Ordered Maps

 Interface with Operating System

 Introduction of Class and Object

 Integrating PHP with Apache Web Server

 Retrieving Information from HTTP Requests

 Creating and Managing Sessions in PHP Scripts

 Sending and Receiving Cookies in PHP Scripts

 Controlling HTTP Response Header Lines in PHP Scripts

 Managing File Upload

 MySQL Server Connection and Access Functions

 Functions to Manage Directories, Files and Images

 SOAP Extension Function and Calling Web Services

 SOAP Server Functions and Examples

 Localization Overview of Web Applications

 Using Non-ASCII Characters in HTML Documents

 Using Non-ASCII Characters as PHP Script String Literals

 Receiving Non-ASCII Characters from Input Forms

 "mbstring" Extension and Non-ASCII Encoding Management

 Managing Non-ASCII Character Strings with MySQL Servers

 Parsing and Managing HTML Documents

Configuring and Sending Out Emails

 Using Local Windows System as a Mail Server

 Sending Out Emails from PHP Scripts

 Sending Out Emails on Linux Systems

 Install PHPMailer on CentOS Systems

 Send Local Emails with PHPMailer

Send Remote Emails with PHPMailer

 Use SMTPS Protocol with PHPMailer

 PHP 5.6 and PHPMailer 5.2

 Install PHPMailer from Source Code

 Image and Picture Processing

 Managing ZIP Archive Files

 Managing PHP Engine and Modules on macOS

 Managing PHP Engine and Modules on CentOS

 Archived Tutorials

 References

 Full Version in PDF/EPUB