Need abuse/postmaster contact for AT&T to resolve IP block Admin admin at
Tue Aug 30 13:22:43 UTC 2016

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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