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3 Messages

Thu, Mar 15, 2018 6:39 PM

RBL IP Unblock / Delist request

I am trying to get our company mail server unblocked. We are not on any of the top 94 RBLs according to (including This system serves email for a medical practice, and the inability to send to or is causing significant disruption to our business operations.


Here is the response we receive from our server when sending to


: host[] said:
553 5.3.0 flpd579 DNSBL:ATTRBL 521< >_is_blocked.For
assistance forward this email to (in reply to MAIL
FROM command)


The system was put into service on its current static IP approximately two months ago, and was already blocked by AT&T on the day it went live. I have to assume it was from a previous owner of that IP or a general block of our hosting service's address range. I have repeatedly emailed in the time since, receiving nothing but automated replies. 


Please let me know if there is any other information you require to unblock our IP.


Best regards,


Jim K.




1 Message

7 months ago


Please delist IP It's sending spam, no marketing email, nothing.

Thank you,

Michael [edited for privacy-please do not post personal or unique information such as but not limited to full names, employee ID numbers, email addresses, phone numbers, account numbers, etc.]

New Member


1 Message

We're also having the same issues. It looks like AT&T has blocked the range of Spectrum Business addresses we use. I even tried some of the IP's that have never been used for email (and we've had them for years) with the same blocking result. I've tried emailing the abuse address multiple times and get an automated response but nothing changes.

Specifically, and 134 are the ones we use.


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