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I have Postfix installed which I am using for SMTP only. It is configured for one of our client's domain and sending newsletters and notifications to the users.

The problem is that because the client owns the domain and receives mail for it, any time there is a message that is bounced or undeliverable, they receive the NDR. This is becoming a nuisance for them and they have asked us to disable sending of these NDR's.

Is it possible to do so? I believe the following parameters are relevant (taken from our current configuration):

notify_classes = resource, software

error_notice_recipient = postmaster


share|improve this question
NDR doesn't mean it's spam, it could be a user who incorrectly entered their email address! With thousands of users, it happens frequently. – blizz May 1 '13 at 14:49
Wouldn't it be better if they actually removed the non-functioning email addresses? Some mailing list software allows you to do that (instead of pretending that the email is valid). – NickW May 1 '13 at 16:40

First of all take backup of and Then follow below steps:

vi /etc/mail/

Change the below line

dnl # define(confPRIVACY_FLAGS',authwarnings,novrfy,noexpn,restrictqrun')dnl



save and exit, run below command

m4 /etc/mail/ > /etc/mail/

Restart sendmail

share|improve this answer
Thanks but I don't have either of those files. I have instead. Where would I put these parameters? – blizz May 1 '13 at 14:47
These directions are for sendmail, not postfix. – Chris S May 1 '13 at 16:29
Earlier you had mentioned both postfix/sendmail, I have sendmail working experience so I gave you answer only for sendmail. – Bobbin Zachariah May 2 '13 at 3:19

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