anyone on from,, smtp?

Terrence Koeman terrence at
Sat May 9 18:32:56 UTC 2020

Hi Joseph,

I've had the same issue that started a year ago. Eventually they removed the subnet, but it was blocked again a week later.

It seems to me they import a third party block list containing my subnet, which re-blocks it shortly after removal, and they won't whitelist. They wouldn't tell me the source (nor the reason).

I've repeated the remove/block cycle a few times and then just gave up and renumbered my mail servers. They don't seem to care. At all.

Your mileage may vary though. If you do get to a solution I'd appreciate hearing about it :) Good luck!

   Terrence Koeman, PhD/MTh/BPsy
     Darkness Reigns (Holding) B.V.

Please quote relevant replies.
Spelling errors courtesy of my 'smart'phone.
From: Joseph Jenkins <joe at>
Sent: Saturday, 9 May 2020 04:36
Subject: anyone on from,, smtp?

> We are getting this messages when sending emails from our domain. We've 
> submitted tickets, but haven't received a response yet. Anyone have any 
> insights? 
> 550 5.7.1 Unfortunately, messages from [] weren't sent. Please 
> contact your Internet service provider since part of their network is on 
> our block list (S3140). You can also refer your provider to 
> [ 
> It's our own address and everything on the Microsoft site says we are clean 
> with no issues. 
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