Need abuse/postmaster contact for AT&T to resolve IP block

Aaron C. de Bruyn aaron at
Wed Aug 31 16:12:42 UTC 2016

Try posting that to the mailop list.
I had been having trouble with for about a month, and I filled out
the form at 3 times with no response.

I posted to mailop a few days ago and they resolved the issue within an

...then a few days later I received the response to the form that my IP had
already been unblocked.  Even though they say they will get back to you
within 2-3 days, it's more like 10-14.


On Tue, Aug 30, 2016 at 6:22 AM, Admin <admin at>

> A few of our exchange IPs get blocked intermittently, but only by ATT. Ips
> are clean, no issues, we’re diligent about finding and fixing these types
> of issues as it has a large impact.
> It would be very helpful to know why the IP below got blocked so we can
> find and fix the problem to prevent further listing. We have a few ips in
> rotation and some have no issue. It’s a “blind” listing, so we only find
> out about it when customers complain that they getting blocked.
> #< #5.3.0 smtp; 553
> 5.3.0 flph399 DNSBL:ATTRBL 521< >_is_blocked.__For_
> information_see_> #SMTP#
> Any info/help would be most helpful.
> Many thanks,
> Postmaster

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