Odd header entries in OUT of Office

[jmritcon...@gmail.com]

This appeared when a user sent internally an email to a colleague in the out of office .
No external servers it was purely internal

Note the References section and the mention of prod.outlook.com. any ideas please



Return-Path: <MAILER-DAEMON>
Delivered-To: ollygroves@mail.********.co.uk
Received: from localhost (localhost [127.0.0.1])
by mail.********.co.uk (Postfix) with ESMTP id 38EC2766E040;
Thu, 13 Jul 2017 00:17:13 +0100 (BST)
Authentication-Results: mail.********.co.uk (amavisd-new); dkim=pass
reason="pass (just generated, assumed good)" header.d=********.com
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=********.com; h=
references:in-reply-to:subject:subject:from:from:date:date
:message-id:received:received; s=default; t=1499901430; x=
1501715831; bh=gMm8T0oi2uCS42rA4AjSkB9EveNFX8tflZn1gh4WqG8=; b=T
QM/G5q1yz1W4zcNWHl1We91TJSOHn8O/yZUxys/wyaqmOP8ISMtcwShBDkFUa5WN
Qp5vK+8D+yd9Al/A8WJHbAaESMnxekEonTiwaBOWbBAEnflS4qWyzIvuuHopfPId
h50rbccwNMlzwOqCSgP3y3/HR1kt5QdbHxEL4b9C9U=
X-Virus-Scanned: amavisd-new at ********.co.uk
Received: from mail.********.co.uk ([127.0.0.1])
by localhost (mail.********.co.uk [127.0.0.1]) (amavisd-new, port 10024)
with ESMTP id 881O3uor1Zir; Thu, 13 Jul 2017 00:17:10 +0100 (BST)
Received: by mail.********.co.uk (Postfix, from userid 214)
id D1EE4766E02D; Thu, 13 Jul 2017 00:17:10 +0100 (BST)
X-Sieve: Pigeonhole Sieve 0.4.1
Message-ID: <dovecot-sieve-1499901430-350955-0@mail.********.co.uk>
Date: Thu, 13 Jul 2017 00:17:10 +0100
From: <bernie@********.com>
To: <olly@********.com>
Subject: AUTO REPLY - Out of Office - Vacation message
In-Reply-To: <C0C12A32-D24D-475D-BC81-BE3692159C4E@********.com>
References: <DB3PR05MB06037BD261...@DB3PR05MB0603.eurprd05.prod.outlook.com>
<5E489C48-741F-4E81-B67D-C10DCBFD368D@********.com>

<DB3PR05MB0603EB7AA8...@DB3PR05MB0603.eurprd05.prod.outlook.com>

<DB3PR05MB06037DEC9F...@DB3PR05MB0603.eurprd05.prod.outlook.com>
<28A4B7D9-C2E0-46B6-8090-322D54F7BB98@********.com>

<DB3PR05MB0603A30113...@DB3PR05MB0603.eurprd05.prod.outlook.com>
<7D6C5743-C313-4287-980F-1E427116F294@********.com>

<DB3PR05MB060362166F...@DB3PR05MB0603.eurprd05.prod.outlook.com>
<3A114FFB-D5E3-4621-B64A-54D4AF6D0CED@********.com>

<DB3PR05MB06038F9A91...@DB3PR05MB0603.eurprd05.prod.outlook.com>
<F5519B54-AAAE-4337-B19E-166A4F54D6BD@********.com>

<DB3PR05MB060350BAA0...@DB3PR05MB0603.eurprd05.prod.outlook.com>
<D08DB7A9-8E73-4273-8847-3FFEF8E9D598@********.com>
<C0C12A32-D24D-475D-BC81-BE3692159C4E@********.com>
Auto-Submitted: auto-replied (vacation)
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit

Hi I'm away from my email and out of the office on holiday. I will be back on July 25th 2017 and will respond then.

[part...@gmail.com]

Hi William,

We are experiencing this same issue and have no idea where it comes from. Specially because we have no Microsoft Exchange server whatsover. We have an Open-Xchange server. The issue appeared also when sending internal e-mails.

Did you ever managed to track down the issue?