Dealing with DNSBL blacklists

Recently a few DNSBL services are flagging emails coming from my server as blacklisted therefore receipt to intended email recipients have been blocked.

One service explicitly stated that IT WAS NOT MY SPECIFIC ip-address that was blocked, but the ip range from which the email originated (I assume 174.138.1.*) and that I should contact the administrators (in a very critical manner) for that ip range to establish what - if anything - they are doing to remove “innocent” servers from the blacklists while preventing the few abusers using your services to spam etc etc.

So here we are!

Your comments would be very much appreciated.


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Site Moderator
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March 2, 2022

Hello there,

DNSBL blacklists can mark whole IP ranges indeed. This is really annoying as often it has nothing to do with your own mail reputation but you’ll still be affected.

Stopping spam is a constant fight, so we have implemented some restrictions on newer accounts, but this still does not guarantee all SPAM will be stopped.

In the meantime, you can use a site like MXtoolbox to check the mail reputation of your IP and send an email to

Their tool will show how you can improve your mail score (outgoing mail delivery).

You can also use a third party mail provider like SendGrid in order to avoid issues like this one. I’ll also recommend checking this article:

You can reach to our support team as well regarding the mail reputation of the whole range.

Hope that this helps!