Bounce Rules

Matt Kettler mkettler at EVI-INC.COM
Thu Oct 27 15:46:04 IST 2005

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Dave Shariff Yadallee - System Administrator a.k.a. The Root of the Problem
> Then what about just making it undeliverable? 

Only if you can do it *before* the end of the SMTP session. Otherwise an
undeliverable message will cause the MTA to generate a bounce, which is
ultimately the same thing as having mailscanner generate a bounce.

The problem isn't the semantics. It's the generation of a DSN message that will
be sent to an address your can be 99.9% sure isn't the author of the message.

(If the message really is spam, there is a 100% chance that both the
Return-Path: and the From: are forged. It's also likely they point to the
mailbox of someone completely innocent, possibly someone who has irritated the

The same applies to most email viruses. The "sender" of the message didn't send
it. It's pure forgery and you're just spamming someone uninvolved by bouncing a
message to them.

If this doesn't make sense to you, Read up on "joe jobs" and "backscatter" or
"blowback" and how they relate to spam and network abuse.

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