Apologies but...Verizon Postmaster?

Charles Sprickman spork at inch.com
Fri Nov 21 18:18:29 UTC 2003

On Thu, 20 Nov 2003, Michael Loftis wrote:

> I have been trying for weeks to get in touch with someone who will respond
> with something other than a form letter at Verizon.  Can someone please
> contact me off-list?  My company (Modwest) is being unilaterally blocked.
> I can't even send mail to abuse, postmaster, etc. from an @modwest.com
> address because of the block in place without a reason and without recourse.

Welcome to the club!

I'm sure someone will get back to you shortly.  But in the meantime, I can
share my experience with this, and perhaps get some opinions on how wise
their "anti-spam" measures are.

VZ was unable to tell me why we were initially blocked, but we were for a
number of days.  Not at the IP level, but at the envelope level; meaning
that if you issued a "mail from:" with the domain in question, you'd get
the "550 You are not allowed to send mail:sc004pub.verizon.net" message.

To this day, we still see some refusals from them like this in our logs.
What I imagine is happening is that the check they do (connect back to
your mx and try to verify the address exists) times out occasionally,
either due to mail server load or connectivity issues.   This causes your
mail to them to bounce with a permanent error.  Not really the best way to
handle mail, but I digress.

Looking at your mxer, I see that the "rcpt to:" is a bit slow.  I wouldn't
be totally shocked if this had something to do with your problem...


> TIA, and I'm sorry for posting here but it's really my last resort (as it
> should be anyones IMHO).
> --
> GPG/PGP --> 0xE736BD7E 5144 6A2D 977A 6651 DFBE 1462 E351 88B9 E736 BD7E

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