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2 Messages

Wednesday, March 4th, 2020 5:02 PM

RBL Removal

I am a postmaster for a dedicated server with a newly assigned IP address on February 23, 2020. Ever since, emails originating from our IP are being blocked on domains. This, despite a stellar record of activity from all domains hosted on our shared server when it was on another IP that never had blocked. We have attempted daily over the course of an entire week to reach the postmaster at as per instructions in emails blocked for our IP. We get an autoresponse, but no human interaction at all.

Bounce messages read like so:

[email scrubbed]

host []

SMTP error from remote mail server after MAIL FROM:<[email scrubbed]>:

553 5.3.0 flpd575 DNSBL:ATTRBL 521< x.x.x.x >_is_blocked.For assistance forward this error to

I would truly appreciate if an ATT postmaster support person would respond. We are growing desperate, as our IP is on zero public RBLs, and we run a properly configured server with all the necessary DNS attributions. We do not send bulk email of any type. Our clients have grown impatient, and rightfully so. This is ridiculous!

-Eric Darling



21 Messages

4 years ago

Good Luck!

We've had the same thing. goes AWOL for months at a time.

And if you ever do get it unblocked, you will never, ever, ever find out why it was blocked to begin with.

AT&T really needs to do something about this. Switch to a contact form with anti-bot captcha system for delisting. Or something. But... I mean... this is AT&T you're dealing with, not exactly the gold standard for actually doing smart things.

Maybe if you're lucky you'll get someone from AT&T to reply back on this forum and tell you that the IP isn't block... despite your evidence to the contrary.

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