Return-Path: <MAILER-DAEMON>
Received: by mail.example.com (Postfix)
        id E2B21594955D; Thu, 29 Apr 2018 23:34:45 +0900 (JST)
Date: Thu, 29 Apr 2018 23:34:45 +0900 (JST)
From: MAILER-DAEMON@mail.example.com (Mail Delivery System)
Subject: Undelivered Mail Returned to Sender
To: kijitora@example.co.jp
Auto-Submitted: auto-replied
MIME-Version: 1.0
Content-Type: multipart/report; report-type=delivery-status;
        boundary="51023C9F5116.1851304236/mail.example.com"
Content-Transfer-Encoding: 7bit
Message-Id: <20180429233445.F309168F0788@mail.example.com>
This is a MIME-encapsulated message.
--51023C9F5116.1851304236/mail.example.com
Content-Description: Notification
Content-Type: text/plain; charset=us-ascii
This is the mail system at host mail.example.com.
I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.
For further assistance, please send mail to <postmaster>
If you do so, please include this problem report. You can
delete your own text from the attached returned message.
                   The mail system
<neko-nyaan@example.ne.jp>: host mail.example.ne.jp[203.0.113.2] said: 550
    5.7.1 Access denied (in reply to MAIL FROM command)
--51023C9F5116.1851304236/mail.example.com
Content-Description: Delivery report
Content-Type: message/delivery-status
Reporting-MTA: dns; mail.example.com
X-Postfix-Queue-ID: 51023C9F5116
X-Postfix-Sender: rfc822; kijitora@example.co.jp
Arrival-Date: Thu, 29 Apr 2018 23:34:45 +0900 (JST)
Final-Recipient: rfc822; neko-nyaan@example.ne.jp
Original-Recipient: rfc822;neko-nyaan@example.ne.jp
Action: failed
Status: 5.7.1
Remote-MTA: dns; mail.example.ne.jp
Diagnostic-Code: smtp; 550 5.7.1 Access denied
--51023C9F5116.1851304236/mail.example.com
Content-Description: Undelivered Message
Content-Type: message/rfc822
Content-Transfer-Encoding: 7bit
Received: from localhost (localhost.localdomain [127.0.0.1])
        by mail.example.com (Postfix) with ESMTP id 352B644C3C17
        for <neko-nyaan@example.ne.jp>; Thu, 29 Apr 2018 23:34:45 +0900 (JST)
Received: from localhost (localhost.localdomain [127.0.0.1])
        by mail.example.com (Postfix) with ESMTP id 46AB8551E097
        for <neko-nyaan@example.ne.jp>; Thu, 29 Apr 2018 23:34:45 +0900 (JST)
From: kijitora@example.org
To: neko-nyaan@example.ne.jp
Subject: Nyaan
Content-type: text/plain; charset=ISO-2022-JP
Message-Id: <20180429233445.70436F9F722D@mail.example.com>
Date: Thu, 29 Apr 2018 23:34:45 +0900 (JST)
Nyaan
--51023C9F5116.1851304236/mail.example.com--