当我使用phpmailer（）发送电子邮件时，在Gmail帐户中收到警告消息

Question

I am using phpmailer() to send email from my website. But when It's sent email I see following warning message.

I can't understand why it's showing and how can I fix this error message. Can anyone tell me about it ?

Following is my code :

<?php
  require_once("mail/PHPMailerAutoload.php");

  $mail = new PHPMailer;
  $mail->setFrom($email);
  $mail->addReplyTo('toemail@gmail.com', 'First Last');
  $mail->addAddress('toemail@gmail.com', 'First Last');
  $mail->Subject = 'PHPMailer mail() test';
  $mail->msgHTML(file_get_contents('mail/contents.html'), dirname(__FILE__));
  $mail->AltBody = 'This is a plain-text message body';
  $mail->addAttachment('mail/images/phpmailer_mini.png');

  if (!$mail->send()) {
    echo "Mailer Error: " . $mail->ErrorInfo;
  } else {
    echo "Message sent!";
  }
  ?>

Answer 1

Easy, you could read about SPF DNS Record.

When you send and email, services like gmail check if the sender ip is the same that the domain of the email, for example:

1. You send an email as "foo@gmail.com" to "bar@hotmail.com". Your server ip is 1.1.1.1

2. Hotmail receives an email from "foo@gmail.com" so check if gmail.com ip (2.2.2.2) is the same as your server (1.1.1.1). The answer is NO, so the email is marked as spam.

3. To avoid that your email will marked as spam, you could use phpmailer using a real google account and provide phpmailer the user and password to send the email.

I tried to explain you the situation very easy on point 2. Real situation is a bit complicated but the logic is the same, check ip sender and origin. Read about SPF (and dkim) because is what are you looking for :) http://en.wikipedia.org/wiki/Sender_Policy_Framework