PHP require_once php path?
You're using an old version of PHPMailer and you're loading it in the wrong way. Please get the latest version and read the docs on loading, or add PHPMailer to your composer.json.
For a manual load you should do:
require '/path/to/PHPMailerAutoload.php';$mail = new PHPMailer;As you're using composer (though you've commented it out), you don't even need to do that much since the composer autoloader will work.
You've also based your code on an old example, so I suggest you update that too using one of the examples provided.