Sending Email: Free PHP & MySQL Tutorial

Topics Covered in This PHP & MySQL Tutorial:

Installing MailHog, Setting up MAMP Pro, Setting up XAMPP, Sending a Test Email

Exercise Overview

PHP's built-in email functionality is elegantly simple—just a single function call can dispatch messages to any recipient. However, the real challenge lies in configuring a reliable mail server for your development environment. Without proper testing infrastructure, you're essentially developing blind, unable to verify that your email features work correctly before they reach production.

This exercise walks you through setting up a professional email testing environment using MailHog, a powerful mail catcher that intercepts and displays all outbound emails from your local development server. We'll configure both MAMP Pro and XAMPP to work seamlessly with MailHog, then demonstrate how to send test emails using PHP's mail() function. By the end, you'll have a robust testing setup that captures every email your application sends, allowing you to debug formatting, verify content, and ensure delivery without spamming real inboxes.

Getting Started with MailHog

MailHog serves as a local SMTP server and web-based email client rolled into one efficient package. Think of it as a black hole for emails—it catches every message sent to it and presents them through a clean, intuitive web interface. This approach eliminates the complexity of configuring actual mail servers while providing complete visibility into your application's email behavior.

For developers working in team environments or attending instructor-led courses, MailHog is typically pre-configured. However, if you're setting up your own development environment, the installation process varies by operating system. The following platform-specific guides will get you up and running quickly.

Running MailHog on Mac

With MailHog installed via Homebrew, launching it becomes a simple terminal command. Windows users can skip to the next section.

1. Open Terminal if it's not already running.

2. Start MailHog with the following command:

   mailhog

3. Press Return. You should see output indicating that MailHog is running and listening on ports 1025 (SMTP) and 8025 (web interface).

4. Keep Terminal open and running in the background—closing it will stop MailHog.

Running MailHog on Windows

1. Navigate to Program Files > MailHog and locate the executable file beginning with MailHog.

2. Double-click the executable and select Run when prompted. This opens MailHog in a Command Prompt window.

3. If Windows Firewall displays a security alert, click Allow access. MailHog needs network permissions to function as a mail server.

4. Leave the Command Prompt window open and running. Minimizing is fine, but closing it will terminate MailHog.

Now that MailHog is running, we need to configure your local development environment to route emails through it. The process differs between MAMP Pro and XAMPP, so follow the section that matches your setup.

Setting up Email: MAMP PRO

MAMP Pro users have the advantage of a streamlined configuration process. Windows users should skip to the XAMPP section below.

1. Launch MAMP PRO if it's not already running.

2. To integrate MailHog, we'll modify the php.ini configuration file, which PHP reads during startup. This file controls core PHP behavior, including mail handling.

   Access the file through File > Edit Template > PHP (php.ini) and select the PHP version currently active in MAMP Pro.

   Note: Your active PHP version appears in MAMP Pro's main interface under the PHP Version column.

3. If MAMP Pro displays a warning about editing system files, click OK to proceed.

4. We need to configure the sendmail_path directive to route emails through MailHog. For your convenience, open sendmail_path.txt from the phpclass folder in your code editor.

5. Select and copy the entire line from the text file.

6. Return to the php.ini file in MAMP Pro.

7. Locate the existing sendmail configuration around line 570. Look for these lines:

   ; For Unix only.  You may supply arguments as well (default: "sendmail -t -i").
   ;sendmail_path =

   Tip: Use Cmd+F to search for sendmail_path if you can't find it manually.

8. Replace the commented ;sendmail_path = line with your copied configuration:

   sendmail_path = /usr/local/Cellar/mailhog/1.0.0/bin/MailHog sendmail

9. The version number in this path must match your installed MailHog version. While 1.0.0 was current when this guide was written, newer versions may be available. To verify your version, paste this path into Finder's address bar:

   /usr/local/Cellar/mailhog/

   The folder listing will show your installed version number.

10. Update the path if necessary, then save the php.ini file.

11. Close the file. MAMP Pro will prompt you to restart the servers—click Yes to apply the changes.

Setting up Email: XAMPP

XAMPP requires configuration of two files to work with MailHog: php.ini for PHP settings and sendmail.ini for SMTP routing. This dual-configuration approach provides more granular control over email handling.

1. Open the XAMPP Control Panel.

2. Next to Apache, click the Config button and select PHP (php.ini) from the dropdown menu.

3. This opens php.ini in your default text editor.

4. Press Ctrl+F to open the Find dialog.

5. Search for sendmail and click Find Next.

6. You'll be taken to a section containing:

   ; For Win32 only.
   ; http://php.net/sendmail-from
   ;sendmail_from = postmaster@localhost

7. Scroll down until you find the XAMPP-specific sendmail configuration:

   ; XAMPP: Comment out this if you want to work with fakemail for forwarding to your mailbox (sendmail.exe in the sendmail folder)
   ;sendmail_path = "\"C:\xampp\sendmail\sendmail.exe\" -t"

8. By default, XAMPP writes emails to disk rather than sending them. To enable actual email transmission through MailHog, modify the configuration as shown:

   ; XAMPP: Comment out this if you want to work with fakemail for forwarding to your mailbox (sendmail.exe in the sendmail folder)
   sendmail_path = "\"C:\xampp\sendmail\sendmail.exe\" -t"
   
   ; XAMPP: Comment out this if you want to work with mailToDisk, It writes all mails in the C:\xampp\mailoutput folder
   ;sendmail_path = "C:\xampp\mailtodisk\mailtodisk.exe"

   Notice how we've uncommented the sendmail line and commented out the mailtodisk line.

9. Save and close the php.ini file.

10. Return to your code editor and open another file.

11. Navigate to File > Open File.

12. Browse to the C:\xampp\sendmail folder.

13. Open sendmail.ini. If you see multiple sendmail files without clear extensions, type sendmail.ini in the filename field and click Open.

14. Locate the SMTP server configuration around line 14:

    smtp_server=mail.mydomain.com
    
    ; smtp port (normally 25)
    
    smtp_port=25

15. Modify these settings to point to MailHog:

    smtp_server=localhost
    
    ; smtp port (normally 25)
    
    smtp_port=1025

16. Save and close the sendmail.ini file.

17. Return to the XAMPP Control Panel. The changes require an Apache restart to take effect.

    Important: If Apache is installed as a Windows service (indicated by a green checkmark), you may need to restart your entire computer for the changes to apply properly.

18. Click the Stop button next to Apache.

19. Click the Start to restart Apache.

    Note: If Apache fails to start or immediately stops after starting, restart your computer, then relaunch XAMPP. The servers should initialize without issues.

Sending an Email

With your testing infrastructure in place, you're ready to send emails using PHP's built-in mail() function. This function provides a straightforward interface to your system's mail transport, making email integration remarkably simple.

The mail() function follows this syntax:

mail(to, subject, message, headers, additional_parameters)

While simple in appearance, proper email construction requires attention to headers, encoding, and formatting standards to ensure reliable delivery and professional presentation.

1. In your code editor, open mail.php from the phpclass folder.

2. Add the following PHP code at the top of the document:

   <?php 
   mail(
       "youremail@gmail.com", 
       "Hello World", 
       "Hello, this is a test message from my PHP application!", 
       "From: youremail@gmail.com\r\n"
   );
   ?>

   The \r\n sequence after the From address is crucial—it represents a carriage return and line feed required by email protocols. Many mail servers will reject messages that lack proper header formatting.

3. Save the file, then test it by navigating to the appropriate URL in your browser:

   • Mac (MAMP): localhost:8888/phpclass/mail.php
   • Windows (XAMPP): localhost/phpclass/mail.php

   Monitor your Terminal or Command Prompt window—you should see MailHog processing the email transmission.

4. To view your captured email, open a browser and navigate to localhost:8025

5. The MailHog web interface will display, showing an inbox containing your test message. Click on the email to view its contents, headers, and formatting.

6. Close any open files. Your email testing environment is now fully operational and ready for development work.

You now have a professional-grade email testing setup that will serve you throughout your PHP development journey. MailHog will capture every email your applications send, allowing you to verify functionality, debug issues, and refine your email features without affecting real users or cluttering actual inboxes.