The block message is 521 DNSRBL: Blocked for abuse

We recently purchased new IP addresses from ARIN, with plans on using one of them for our external and internal email delivery. We set up a reverse lookup and a SPF record for the newly purchased IP to prevent being classified as spam. We tested the functionality of the PTR and SPF record successfully using varies internet tools like dnsstuff.com, mxtoolbox.com, and kitterman.com. Unfortunately, when we send emails to any AT&T or Network Solutions hosted email we are being block as a spam abuser. I checked varies spam database tools and our IP addresses are not listed, but we are still being blocked by both AT&T and Network Solution. The block message is 521 DNSRBL: Blocked for abuse. In an attempt to be proactive, I contacted Network Solution and was told that each recipient would have to request we be whitelisted, and AT&T directed me to an online form that I submitted to be removed from the blacklist. Unfortunately, we are still not able to send emails to either AT&T or Network Solutions hosted emails. Our mail server IP address is 74.112.99.25, which resolves to mail.abcsupply.com. Does anyone have any suggestions on where to turn next? Is it possible they are blocking us based on old information from the previous IP address block owner? Any help tracking this down would be appreciated.

Derrick Wash
Microsoft Systems Administrator
ABC Supply Company Inc
Office: (608)368-2214
Fax: (608)363-0214

My experience in the past is that it can take a good amount of time for ATT to remove you from their black list. It's been as short as 24 - 48 hours and as long as a couple weeks and required follow up contact with support. They're a big company and they get a lot of requests. I've not dealt with Network Solutions or their RBL list as far as how to get whitelisted. But it sounds like they manage it in a way where the recipient has to accept email from you. It's probably not practical but can you contact the recipients on Network Solutions via another method to have them whitelist you?

From the sounds of t the IP address you purchased was previously used by a spammer and now you're paying the price for it. Perhaps there are contacts on this list from ATT/Network Solutions that can contact you off list to help you resolve that.

Good luck!

Mike Schuler
a guy

I would say the first step is to find an immediate workaround for your end
users - maybe bring up a VM on AWS or some other cloud provider to use as
an SMTP relay while you work out the blacklist issue. If you run into
blacklist issues after that, you may want to take a very close look at your
outbound mailflow to make sure your organization isn't sending out messages
that could be categorized as spam.

Getting IPs removed from a provider blacklist can be time consuming. You
may be lucky enough to reach a clueful contact at the providers you
mentioned on this list - but if you don't, you will have to navigate the
removal process with each provider that has blacklisted you.

We recently purchased new IP addresses from ARIN

No, actually, you didn't. You were assigned the use of the addresses, based on need. Just as a radio station does not "purchase" spectrum.

Our mail server IP address is 74.112.99.25. Is it possible they are blocking us based on old information from the previous IP address block owner?

Quite likely, yes.

John LeCoque's suggestions seemed quite sound:

I would say the first step is to find an immediate workaround for your end
users - maybe bring up a VM on AWS or some other cloud provider to use as
an SMTP relay while you work out the blacklist issue. If you run into
blacklist issues after that, you may want to take a very close look at your
outbound mailflow to make sure your organization isn't sending out messages
that could be categorized as spam.

                                -Bill

> Our mail server IP address is 74.112.99.25. Is it possible they
are blocking us based on old information from the previous IP
address block owner?

Quite likely, yes.

Found it to be of use for this type of question. Registration required.
Geolocation information often needs updating for these "recycled" ranges.

/JF

Quite unfortunate..

These days, when allocated 'new' IPV4 space you really have to do a little homework to make sure it 'clean'.

I would suggest that you run your CIDR block through http://multirbl.valli.org/lookup/.

IF it's mostly clean and not on hardcore lists such as SpamHaus ROKSO, then there's hope.

Whatever lists your netblock is on you will just have to contact thier abuse dept. and explain your predicament and
stay on top of it.

Sounds like you are well on your way to doing that..

Good luck.

Carlos.

Not a good idea. It's a best practice to refuse *all* email traffic
out of Amazon's cloud because (a) it's a prodigous source of spam and
other forms of abuse and (b) Amazon absolutely refuses to lift a finger
to address the problem. (Just try submitting an abuse report and notice
all the hoop-jumping they've put in the way in a quite obvious, deliberate
attempt to make it as difficult as possible.)

---rsk