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I am not entirely sure whether this belongs here, so feel free to redirect me in case I posted this to the wrong board. I have a small apache2 webserver (raspberry) registered under the domain (currently not online, so don't even try :) but when I woke up today I found about 40 of these email messages in my Inbox:

This is an automatically generated Delivery Status Notification



Delivery to the following recipient has been delayed:

Message will be retried for 2 more day(s)

Technical details of temporary failure: Google tried to deliver your message, but it was rejected by the server for the recipient domain by [].

The error that the other server returned was: 450 4.1.1 : Recipient address rejected: unverified address: unknown user: ""

----- Original message -----

DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=20120113; h=x-received:message-id:date:from:to:subject:content-type:x-cron-env :x-cron-env:x-cron-env:x-cron-env:x-cron-env; bh=k/8GlT8DBvBIJzBOOfw8qR0kGPzj7m9ZR/aj+JOKBhg=; b=Ne2qnI58Cj7zjdBGlw0UqHyGltmAiVc1acnD9Wo207Y9T0w1h3TUWb73E1VZwdJm3j kxxNCrsiKLKUfyUmUJPataGPPOnBR/I0wV8WcQPlxu5vRn2omTracmId4W11hib9EUdK OgHs1NJZw8h1zIBijkz6gDgVKkD6P2PlrtvlCGvqJiPk6N8vSksBshq2ACuDamLktKFq gkWZke9OcfkjpqEri1aiFoenwrsi6uFNLlVRx3BED/Igcn01YqsQiHejlSDMiol4JVFx 1OATY448EinQj2XJJSGW+bNZckjo5S9ErxROI8uff2ic+DONkpSn9BFDYPZ1MqmlwguG zwwQ== X-Received: by with SMTP id fi3mr5153452bkc.58.1365097204482; Thu, 04 Apr 2013 10:40:04 -0700 (PDT) Return-Path: Received: from ( [MY IP]) by with ESMTPS id o2sm6728296bkv.3.2013. (version=TLSv1 cipher=RC4-SHA bits=128/128); Thu, 04 Apr 2013 10:40:03 -0700 (PDT) Message-ID: <> Received: by (sSMTP sendmail emulation); Thu, 04 Apr 2013 19:40:01 +0200 Date: Thu, 04 Apr 2013 19:40:01 +0200 From: root To: root Subject: Cron test -x /etc/init.d/sendmail && /usr/share/sendmail/sendmail cron-msp Content-Type: text/plain; charset=UTF-8 X-Cron-Env: X-Cron-Env: X-Cron-Env: X-Cron-Env: X-Cron-Env:

/usr/share/sendmail/sendmail: 899: /usr/share/sendmail/sendmail: /usr/sbin/sendmail-msp: not found

I pretty much have no idea what could cause this Error... I did never send any email to the address, nor do I have sendmail installed (which seems to cause the error). any clues? thanks!

share|improve this question
Did this mail server EVER work right? Are you sure you want your MX records pointing at 'cause they do. :) – Ƭᴇcʜιᴇ007 Apr 6 '13 at 15:35
Thing is, I don't have any mail server... If I need to send emails from the apache2 server I usually use gmail as a relay to send my emails. (I use ssmtp and "mail" to do the job. Could you explain what is and how I could change it? Thanks so far! – YumTum Apr 6 '13 at 15:40
up vote 0 down vote accepted

The servers (not sure what those actually are) are set in the MX record (DNS mail server entries) for

Assuming that this is a bounce message from Gmail, it looks like you sent an email (via gmail) to yourself (From: root To: root).

Root presumably has the email address "", and it's been rejected by the mail servers for ( as an unknown user.

To stop these message you'll need to create/acquire a mail server for the domain and update your DNS MX records to point to it so that you can receive the emails. Then you won't get the bounces messages. :)

Or perhaps just change Root's email address to your gmail account.

share|improve this answer
As always the solution is so simple: I now changed the roots email address (didn't even know it was set) to my gmail address. Hopefully the emails will stop now! :) Thanks a lot! – YumTum Apr 6 '13 at 16:58
Well, half the problem is solved, I just received an email, reading: /usr/share/sendmail/sendmail: 899: /usr/share/sendmail/sendmail: /usr/sbin/sendmail-msp: not found. So now its only sendmail ... do I have to install sendmail? Why, or what is sending these emails anyway? The email Subject is: Cron <smmsp@raspberrypi> test -x /etc/init.d/sendmail && /usr/share/sendmail/sendmail cron-msp. So its a cronetab? – YumTum Apr 6 '13 at 17:03
I think my answer still stands for the original question; figuring out what's actually sending the mail based on this new information seems like a candidate for a whole new/different question. :) – Ƭᴇcʜιᴇ007 Apr 6 '13 at 17:11
I agree, I mark it as solved. Thanks! – YumTum Apr 6 '13 at 17:19

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