Author: Renaud Allard Date: To: David Saez Padros CC: Exim, Users, Peter Bowyer Subject: Re: [exim] Ultimate spam defense - check for the sender MX record
David Saez Padros wrote: > Hi !!
>
>>> I couldn't agree more - if they've left something out of their SPF
>>> policy, they should fix it - and if they don't get any pain, they
>>> won't.
>>
>> Indeed, but in this case, the one being really hurt was my client which
>> didn't receive his licenses. Trying to explain commercial people (the
>> ones you get on the phone when calling for a license delivery problem)
>> that their mail containing the licenses was being refused by our server
>> because something was wrong in their DNS is like the quest of the grail.
>
> you just need to say to the client that the owner of the remote domain
> has explicity ask you to refuse that email.
>
That's what I said to the client and he did understand that. However,
that didn't give him back the mail he needed.
I know that all the art of antispam is to block spam while avoiding
blocking badly configured servers. And many new techniques and
approaches are good, but as always, people trying to implement them make
mistakes which can make things worse.
As a matter of fact (and experience), I think blocking on SPF result
only may not be a very good idea, at least for the moment.
