Bouncing messages with missing From: info

Rick Cooper rcooper at
Wed Apr 17 13:39:31 IST 2013



From: mailscanner-bounces at
[mailto:mailscanner-bounces at] On Behalf Of Jerry
Sent: Wednesday, April 17, 2013 1:22 AM
To: MailScanner discussion
Subject: Re: Bouncing messages with missing From: info

Null sender is RFC standard for NDRs.
[Rick Cooper] 
Exactly hence the admonishment not to reject based on null sender. However I
once got a huge mess of bounce spam directed at three specific, valid, users
and set a rule that rejected emails to those users with a null sender until
it seemed to cease (which took about a month). The thing that really pissed
me off is we publish SPF with a hard fail so there was really not valid
reason that either end should have had to deal with it, except the bouncing
systems were to lazy to implement SPF checks on their end. IMHO even if you
do not implement SPF on your end you should at least check SPF for inbound

On Wed, Apr 17, 2013 at 3:11 AM, Rick Cooper <rcooper at> wrote:

Raymond Norton wrote:
> I am using MailScanner 4.84.5 with postfix. I have one relay domain
> getting hit hard by  non delivery notices which are missing any info
> in the "From" field.
> Is there a rule I can add to postfix that will bounce messages like
> this?
> Raymond

You should not bounce or reject anything based on null senders as that
prevents legitimate bounces.
You do not state if the TO addresses are valid, if they are you will have to
deal with it unless you see a pattern of valid users that are getting the
bounces, in which case (I have had to do this in the past) we deny or
redirect bounces to that/those users that also have a null sender. If they
are invalid then you should be rejecting them at RCPT time.

My philosophy is I NEVER bounce anything. Once accepted it's my problem and
I do not accept non deliverable emails, or emails that are supposedly coming
from my domain but not one of my servers or any Hard fail SPF result or
failed DKIM, or other criteria. Once I take it it's my problem so I just
don't take problems


MailScanner mailing list
mailscanner at

Before posting, read

Support MailScanner development - buy the book off the website!



Jerry Benton

Mailborder Systems

-------------- next part --------------
An HTML attachment was scrubbed...

More information about the MailScanner mailing list