On 15/12/2019 11:42, Alessandro Vesely wrote:
The reason why SMTP requires to accept such stuff, AFAIUI, is to allow a
server to still be able to do its job. Is it so? Compare that to, e.g.,
where a certificate error can shut a server up.
It was so, back in the days when mailservers were few and trustworthy
and before spammers and marketers arrived.
Now, it's a flag for a system that the operator cannot be bothered to
set up properly, or was never supposed to be sending mail at all
(and has been hijacked).
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