Hi !!
>> In fact any callout that you receive is another bounce that you avoid
>> receiving, so if you ever faced that situation you will really prefer
>> callouts than bounces.
>
> Personally I'd prefer that more mail admins learn to reject mail
> outright, rather than accept and bounce. Then I wouldn't have to deal
> with the bounce or a callout.
This could be in a perfect world, we always try to reject at smtp time
but not all people could do that. Some very large spanish providers
(and many others around the world) just accept anything on the mx hosts
and then route the message to other hosts that know if the user really
exists so they cannot reject unknown users at smtp time.
I have been thinking for some time to setup a domain based dns list
that will list either domains that do not accept null senders, domains
for which it's mx hosts accept everything at smtp time and domains that
it's postmaster has expressly asked to not receive callouts. This list
will be used to avoid doing callouts on the listed domains because
either it will have no meaningul result or because that domain does not
like callouts.
--
Best regards ....
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David Saez Padros http://www.ols.es
On-Line Services 2000 S.L. e-mail david@???
Pintor Vayreda 1 telf +34 902 50 29 75
08184 Palau-Solita i Plegamans movil +34 670 35 27 53
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