Mail Server best practices - was: Pandora's Box of new TLDs

Jean-François Mezei jfmezei at
Sat Jun 28 21:56:23 UTC 2008

re: reverse DNS and emails.

There are well documented and fairly simple tasks to reduce spam.
requiring rdns, using rbls and blocking certain IP blocks goes a long way.

The biggest problem however are outfits like microsoft whose hotmail/msn
properties have undocumented logic which confirm reception of the
message at the SMTP/821 level but then proceed to discard the email
instead of delivering it to the person's inbox (or spam folder). Because
they are unfortunatly popular, this means that sending email to users of
those systems has become untrustable since you need to phone them to
ensure they got the email.

And it is impossible to talk to a "postmaster" at hotmail to know why
hotmail sometimes/often doesn't like your emails even though you abide
by standard rules. (rdns, spf etc)

Spam getrs you more than you bargained for, but you still get your
legitimate emails. But hotmail/MSN discard legitimate emails without
warning and that makes SMTP untrustable and this is a far more serious

The original mantra of either discarding the email during SMTP
conversation, or sending a non delivery notification should be strictly
adhered to. When email becomes unreliable (thanks to microsoft), people
stop using it.

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