Messages classified as spam (deleted) create a return message to the sender
Problem reported by EDUARDO HEISLER - 2/27/2020 at 11:07 AM
On our server, we use different actions for spam according to the score ... When they reach 60 points, the action is to delete the message.

When this happens, in addition to deleting, SmarterMail is sending a return message to the sender, stating that the delivery failed (DELIVERY_STATUS_FAILURE).

We have a huge queue of emails being sent to a spammer's address, which probably doesn't exist.

This has caused an increase in CPU usage.

9 Replies

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Employee Replied
Employee Post
Thank you for posting this issue here. We believe we have found a fix and it should be in the next BETA build. Please let us know whether or not it helps the situation.
echoDreamz Replied
Yep, we just got alerted to this, 3 of our gateway IPs were blacklisted due to this.
Manuel Martins Replied
We are having the same problem on our production server with version 7242.
Robert Simpson Replied
One thing SM also does is send read receipts and delivery receipts with no way to disable it.  I ended up writing a Windows Service that monitors the spool and deletes them.  They do not trigger the configurable spool command-line process.

Good afternoon 

We reported this some time ago in a ticket we opened: 

- Smartermail automatically sends confirmation of delivery of the message, when requested. We need to disable the sending of notification emails for incoming messages, because this is a way for spammers to know that the account really exists and to increase the sending of messages.
Manuel Martins Replied
How do you identify those messages in the spool ?
Robert Simpson Replied
I wrote a service in C# to do it.  Basically I created a FileSystemWatcher instance to watch the spool folder.  When a new file appears in the spool, I read the headers into an array.
Then I check the headers.  I check for two things:

1.  The "From" line contains "System Administrator" 
2.  "Content-Type" is of type "multipart/report" and also contains a "report-type=delivery-status"

If a spool e-mail contains those two things, I move the file to a "Spam" folder outside the spooler so I can review it later.  At first I reviewed them all, but now I mainly clean that folder up weekly without even bothering to look anymore.

It would be a ton easier if SM just triggered the configurable spool proc executable for these.  It currently doesn't, so there's no other way to catch them.

You also cannot strip the receipt request from the original e-mail using the spool proc executable, because the delivery report is submitted before the spool proc gets it.

Also, I did not want to deny my users the opportunity to request receipts, and there's no reasonable way for me to try and be selective.

I want SM to stop sending them, but I don't want my users to not be able to request them.

Manuel Martins Replied
Thanks for the info Robert Simpson
Andrea Free Replied
Employee Post
Hi everyone,

This concern has been addressed. A new "Enable Delivery Status Notifications (DSN)" option is available in Protocol settings > SMTP In. This change will available in the next upcoming BETA build and the upcoming public release as well. 

Andrea Free
SmarterTools Inc.


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