Issue Plesk sends out mails to MAILER-DAEMON@server5.configcenter.info

[SteffB]

I think our Pleks 12.5.30 Update #36 started to send out mails since yesterday to the mentioned adress and we get the following undelivery message every 10 minutes:

Why do the system try to send mails to this adress and why (Client did not present a certificate) dose the server dont accept them?

Thanks Stephan

Diagnoseinformationen für Administratoren:

Generierender Server: server5.configcenter.info

MAILER-DAEMON@server5.configcenter.info
#< #5.2.0 x-unix; procmail: Couldn't create "/var/mail/nobody" procmail: Unable to treat as directory "//Maildir" procmail: Lock failure on "//Maildir.lock" procmail: Error while writing to "//Maildir"> #SMTP#

Ursprüngliche Nachrichtenkopfzeilen:

Received: from webserver.symbicom.de (webserver.symbicom.de [217.151.145.130])
(using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not
present a certificate) by server5.configcenter.info (Postfix) with ESMTP id
BF7F0FE00E for <MAILER-DAEMON@server5.configcenter.info>; Tue, 14 Jun 2016
07:40:08 +0200 (CEST)
Received: from 127.0.0.1 (webserver.symbicom.de [127.0.0.1])
by webserver.symbicom.de (Postfix) with ESMTPA id 0F33CAC1E73
for <MAILER-DAEMON@server5.configcenter.info>; Tue, 14 Jun 2016 07:40:07 +0200 (CEST)
Date: Tue, 14 Jun 2016 07:40:07 +0200
MIME-Version: 1.0
Content-Type: text/html; charset="utf-8"
Content-Transfer-Encoding: 8bit
From: =?utf-8?Q?Symbicom=20AG?= <[[an internal mail adress from our domain]]>
To: <MAILER-DAEMON@server5.configcenter.info>
Subject: =?utf-8?Q?Neues=20Ticket:=20Undelivered=20Mail=20Returned=20to=20Sender=20[ID:25782228]?=
Sender:
Message-ID: <20160614054007.0F33CAC1E73@webserver.symbicom.de>