I need step by step instruction to fix this error. I found two files in the /var/mail folder. root and www-data. When I opened them, the messages contain some information as follows.
The original message was received at Thu, 5 Oct 2017 03:33:58 GMT from localhost [127.0.0.1]
----- The following addresses had permanent fatal errors ----- firstname.lastname@example.org (reason: 550-5.7.1 [18.104.22.168 1] Our system has detected an unusual rate of)
----- Transcript of session follows ----- … while talking to gmail-smtp-in.l.google.com.:
DATA <<< 550-5.7.1 [22.214.171.124 1] Our system has detected an unusual rate of <<< 550-5.7.1 unsolicited mail originating from your IP address. To protect our <<< 550-5.7.1 users from spam, mail sent from your IP address has been blocked. <<< 550-5.7.1 Please visit <<< 550-5.7.1 https://support.google.com/mail/?p=UnsolicitedIPError to review our <<< 550 5.7.1 Bulk Email Senders Guidelines. a65si236585pgc.201 - gsmtp 554 5.0.0 Service unavailable
–v953a0qK031348.1507174560/wordpress-1gb-sgp1-01 Content-Type: message/delivery-status
Reporting-MTA: dns; wordpress-1gb-sgp1-01 Received-From-MTA: DNS; localhost Arrival-Date: Thu, 5 Oct 2017 03:33:58 GMT
Final-Recipient: RFC822; email@example.com Action: failed Status: 5.7.1 Remote-MTA: DNS; gmail-smtp-in.l.google.com Diagnostic-Code: SMTP; 550-5.7.1 [126.96.36.199 1] Our system has detected an unusual rate of Last-Attempt-Date: Thu, 5 Oct 2017 03:36:00 GMT
–v953a0qK031348.1507174560/wordpress-1gb-sgp1-01 Content-Type: text/rfc822-headers
Return-Path: www-data@wordpress-1gb-sgp1-01 Received: from wordpress-1gb-sgp1-01 (localhost [127.0.0.1]) by wordpress-1gb-sgp1-01 (8.15.2/8.15.2/Debian-3) with ESMTP id v953XwqK031346 for firstname.lastname@example.org; Thu, 5 Oct 2017 03:33:58 GMT Received: (from www-data@localhost) by wordpress-1gb-sgp1-01 (8.15.2/8.15.2/Submit) id v953XwCo031338; Thu, 5 Oct 2017 03:33:58 GMT To: email@example.com Subject: =?UTF-8?B?W+GAseGAnOGAt+GAnOGArF0gUGFzc3dvcmQgUmVzZXQ=?= X-PHP-Originating-Script: 33:class-phpmailer.php Date: Thu, 5 Oct 2017 03:32:58 +0000 From: WordPress firstname.lastname@example.org Message-ID: email@example.com X-Mailer: PHPMailer 5.2.22 (https://github.com/PHPMailer/PHPMailer) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8
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