Re: Email Bouncebacks - Backscattering

[Kyle Wheeler <kyle-mutt@xxxxxxxxxxxxxx>]

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On Monday, May  5 at 10:08 AM, quoth Joseph:
> There is an article on slashdot on "email bounceback" Is the solution as 
> simple as including custom header and filtering it with procmail?

Wouldn't that be nice?

Putting a custom header in all your outbound emails and watching for 
it in bounces is nice BUT you cannot rely on valid bounces containing 
all of the headers of the email they're bouncing. For example, "out of 
office" emails often contain *nothing* of the original email. The same 
is true of mailing list challenges (which will have a sender, so they 
count as backscatter, but aren't technically bounces). DSN emails also 
frequently don't contain full headers; they may just contain the 
subject line of the message they're responding to.

Valid bounces can be relied upon to contain only one piece of 
information from the email they are bouncing, and that one piece of 
information is the envelope address you sent from.

Since that's the only piece of your original email that you can 
*guarantee* will be in a valid bounce, that's the only piece of your 
original email that you can monkey around with. A good way of 
monkeying around with it is BATV, but that has its own problems that 
need to be worked around (e.g. subscriber-only mailing lists typically 
check the envelope sender against the list of subscribers).

~Kyle
- -- 
To believe in God is impossible---to not believe in him is absurd.
                                                            -- Voltaire
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