Well, when you reject at SMTP-time, it is the sender MTA's
responsibility to send the bounce. In the case of a legitimate email
(with a mistyped address or something), the sender MTA will usuaully do
so. In the case of a spam, we really don't care what it does ;)
Of course, it would be nice if all MTA's were smart enough to actually
include the text after your 5xx code in the bounce message they
generate ;)
Too bad there is no effective way to fully verify the deliverability of
remote addresses..
Of course, you could perhaps establish a list of 'legitimate' mail
servers, and accept messages from those hosts, and send the bounce. Any
others would get rejected at SMTP time..
On Fri, 8 Sep 2000, Philip Hazel wrote:
> On Fri, 8 Sep 2000, Brian K. West wrote:
>
> > Philip,
> > Yes I did flame him really really bad.. :) I was just wondering if it
> > was bad to accept mail like this then bounce it, or verify recipient.
>
> It is entirely up to you which you do. Either is acceptable. Many people
> prefer to verify recipient, because it reduces the number of failed
> bounce messages in the age of spam with forged senders. I find this
> sad, because it prevents you from providing a service to send back a
> helpful message about unknown local parts. We had such a service, giving
> hints on common mis-typings and referring to our web page, and gradually
> over the years the domains for which it is active have been cut back and
> cut back, as more and more spam comes with forged senders. It pisses me
> off, because the spammers are preventing me from running a service I
> want to provide to legitimate senders.
>
>
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