Mail loops on delivery failures via an alias


We have a server that uses postfix to forward emails for certain aliases to lists of people. Most of these people use a system (e.g. Gmail) that will reliably reject the emails if inboxes are full or they match malicious attachments, and postfix will then return a delivery failure message to Helpmonks.

When this happens, Helpmonks takes the failure email and creates a new conversation, which is then sent out to all users, causing a storm of emails. I’m sure Helpmonks already tries to identify bounce messages and treat them appropriately, but for some reason it’s not doing so in this case.

I’ve tried adding our server’s failure address to the Blacklist, but that doesn’t seem to work (possibly because it’s case sensitive but lower-cases the address?).



Here’s an example email:

received: from ( [2001:ba8:1f1:f298::2]) by (Haraka/2.8.18) with ESMTPS id 415BB673-E74E-44A8-AAD0-7B088157A499.1 envelope-from <> (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES128-GCM-SHA256 verify=FAIL); Tue, 05 Jun 2018 14:58:00 -0400by (Postfix) id DB82E1FC60; Tue, 5 Jun 2018 18:57:59 +0000 (UTC)by (Postfix) id D91CA1FC5A; Tue, 5 Jun 2018 18:57:59 +0000 (UTC)
delivered-to: emf-<stripped>
date: Tue, 5 Jun 2018 18:57:59 +0000 (UTC)
from: (Mail Delivery System)
subject: Undelivered Mail Returned to Sender
to: <stripped>
auto-submitted: auto-replied
mime-version: 1.0
content-type: multipart/report; report-type=delivery-status; boundary="6AD801FC60.1528225079/"
message-id: <>

This is the mail system at host

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

(expanded from ): host[] said: 550 5.7.1 Message refused due to
content violation: - contact if this is in error (in reply to end of DATA


Also, there seems to be no way to temporarily turn off notifications for a mailbox - the default doesn’t affect any existing users.



You may try creating a workflow instead to filter failure messages.

On your Mailbox settings, select workflow.
Under Conditions, select “email sender” and add the failure address.

Next is on the Actions field,select “change the status to” and pick the status you prefer (i.e. close, spam or trash)

Hope that helps!


We are looking into the bounce messages.

Regarding notifications, the one in the mailbox do NOT overwrite the user ones. If you are an admin you can edit the notification settings of each user under “Helpmonks users”.


We’ve now added an update to our incoming servers to not send bounce messages to the same user within an hour again. This should help with those bounce messages.