Have a look at this send() function here
$this->Body = preg_replace('/\$' . $key . '\b/', $value, $this->Body);
$this->Body_html = preg_replace('/\$' . $key . '\b/', $value, $this->Body_html);
$this->AltBody = preg_replace('/\$' . $key . '\b/', $value, $this->AltBody);
}
/**
* overloads PHPMailer::Send() to allow for better logging and debugging SMTP issues
*
* @return bool
*/
public function send()
{
//Use these to override some fields for tests when debugging SMTP issues:
//$this->Host = "smtp.myserver.com";
//$this->From = 'me@here.com';
//$this->FromName = 'My Name';
//$this->Sender = 'me@here.com';
//$this->Password = 'wrong';
//$GLOBALS['log']->debug("PHPMailer Send Function: { FromName: $this->FromName From: $this->From Host: $this->Host UserName: $this->Username }");
there are several commented lines there that you can use to troubleshoot. This will help you see what is actually being sent out to the SMTP server, edit those fields for tests, and get a full SMTP log.