Hi Roberto,

Greetings..!!

I am holding a doubt regarding NDR while evaluating Spam Filter for our Mail Server. Here it goes..

In SpamFilter > Configuration > Options , there is a option to allow/block Empty "Mail From" .

We use MS SMTP for Outgoing Mails and another SMTP for Only Receiving Mails ( MX record in DNS points to this).

Now when I enable Empty "Mail From", the NDR sent by MS SMTP are being simply rejected by SpamFilter and also some other mails received from outer domains with Empty Mail From , where as RFC 1123 5.2.9 (More information points to RFC-821 Page 15) says that A empty reverse path MUST be supported.

I realise that SpamFilter just acts as a Filtering Proxy for my Incoming SMTP server and ofcourse validates Incoming mail based on the settings & MAPS lookups.

If I uncheck the Empty "Mail From" , the SpamFilter may allow NDR generated by my MS SMTP and also other mails with Empty Mail From.

How do i make sure that only NDR related mails alone are accepted by SpamFilter and reject other Emails with empty Mail From. I am using v1.2.0.178.

Best Regards

Thirumal Reddy M

System Admin / SQL DBA.

Thirumal,

SpamFilter can not make a distinction between NDRs and Spam email with an empty mail from address. That is why we do not recommend enabling that filter unless the sys admin specifically wishes to reject ALL email, including NDRs, with an empty return address. Some admins requested the option, that is why it is there.

Roberto F.
LogSat Software