Return-Path: <existing@bar.com>
From: Foo Bar <existing@bar.com>
To: team@bar.com
Subject: This is a topic to a group from an existing user
Date: Fri, 15 Jan 2016 00:12:43 +0100
Message-ID: <32@foo.bar.mail>
Mime-Version: 1.0
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Hey there, this is an email to a group mailbox from an existing user.