Filter on

Dean Gaudet dgaudet-list-nanog at
Thu Sep 25 01:29:08 UTC 1997

FWIW I too see this when attempting from one address, but not from
another.  Both addresses are in MCI customer-owned ip blocks.  Both
addresses have correct double-reverse lookups.  It's more than just a bit
annoying ... especially when I receive mail from MCI's noc and cannot
reply to it unless I go through hoops to route it through another box.


On Wed, 24 Sep 1997, Kevin Houle wrote:

> On Wed, 24 Sep 1997 14:45:01 -0400 (EDT)
> Jared Mauch <jared at> wrote:
> > Kevin.. it works if you give the proper machine name in the HELO
> MCI's iNOC pretty much confirmed there was a filter in place,
> as did the systems person I finally reached thanks to some
> key responses from this list. Probably a spam relay block of
> some kind. The '550 Access denied' reponse is that they use
> in their SMTP filters. was down for 
> two hours and counting when I got them on the phone, so with 
> local MCI users not being able to send mail, I was not a high 
> priority :)
> At any rate, the 'HELO' statement is a result of
> host masquerading ( Same thing happens with a
> FQDN :
> 220 ESMTP Sendmail 8.8.5/8.8.5; Wed, 24 Sep 1997 15:16
> :25 -0400 (EDT)
> 250 Hello kevin at [], pleas
> ed to meet you
> MAIL FROM:<kevin at>
> 550 Access denied
> Kevin

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