10-26-2016 3:27 PM
Hi, I'm the syadmin of an ESP. For some reason most of our users with ATT email addresses are unable to receive emails from the system. We've tried numerous times reporting the issue to ATT blocks, however the issue still exists and our users are getting frustrated. Can you help please?
This is the ATT error message from our email server. We use Elastic Email as our Email service provider. They believe you are blocking our domain for some reason, as they have already moved us to another ip.
Here's an example of the error we are getting:
553 5.3.0 alph154 DNSBL:RBL 521<188.8.131.52 >_is_blocked.For information send an email to firstname.lastname@example.org
This affects most of the IPs in our netblock (184.108.40.206/24) but not all.
We've reported this many times now and gotten no reply. It's been over a month. We've gone through every remediation step listed here:
Filled out the form here a number of times:
I tried this form as well:
Any help would be much appreciated!
Solved by: Go to Solution.
08-29-2018 5:51 PM
We had a similar problem and when we checked independent blacklists it said we were clear.
Can you help us resolve the issue?
553 5.3.0 alph735 DNSBL:ATTRBL 521< 220.127.116.11 >_is_blocked.For assistance forward this email to email@example.com (in reply to MAIL FROM command)
09-01-2018 6:00 AM
we need to solve this issue.
we would send an email to @sbcglobal.net demain
Domain do be unblocked: @barrocoitalia.com
" host al-ip4-mx-vip2.prodigy.net[18.104.22.168] said:
553 5.3.0 alph732 DNSBL:RBL 521< 22.214.171.124 >_is_blocked.
09-03-2018 5:22 PM
I'm having the same problem here. Seems like AT&T has blocked all IP addresses within the Amazon Web Services (AWS) IP range (which is huge) and are unblocking them one at a time.
Please unblock the following IP addresses.
I've emailed the firstname.lastname@example.org address several times with all requested info and have heard not a single response. Most of my users are bailing from AT&T/SBCGlobal/PacBell over this and getting email addresses elsewhere (gmail/yahoo, etc).
09-06-2018 3:22 AM
Our company is having the same issue
We are trying to email two customers at Prodigy.net and Sbcglobal.net and they keep getting bounced back to us with the following error,
host ff-ip4-mx-vip1.prodigy.net[126.96.36.199] said: 553 5.3.0 flph823 DNSBL:RBL 521< 188.8.131.52 >_is_blocked.For assistance forward this email to email@example.com (in reply to MAIL FROM command)
I have checked all 3 of our external IP addresses 184.108.40.206/137/138 against multiple blacklist sites and everything comes back clean.
09-07-2018 1:37 AM
AT&T also blocked our IP 220.127.116.11, which is definitely an IP with good reputation. Our clients are constantly complaining their email rejection. Error message saying:
553 5.3.0 alpd678 DNSBL:RBL 521< 18.104.22.168 >_is_blocked.For assistance forward this email to firstname.lastname@example.org (in reply to MAIL FROM command))
Please help to get it unblocked.
09-12-2018 5:37 PM
I am the Marketing Manager for Bizworldusa, and we are conducting the legal business
last 4 years. We have similar problem from last few days our clients are not getting an emails from us and few were
bounced back as below. I did forwarded to the email to the given address but no
response from last 7 days. Wondering what is the method to remove the block / resolve
the issue. Could you help us on block removel.
flpd572.prodigy.net rejected your message to the following e-mail addresses:
flpd572.prodigy.net gave this error:
flpd572 DNSBL:ATTRBL 521< 22.214.171.124 >_is_blocked.For assistance forward
this email to email@example.com
- edited 09-13-2018 10:15 AM
I got mine resolved! Here's what I did. I set up an alias in our postfix admin to forward messages sent to our return-path address to my own mailbox. I've had to wade through a TON of undeliverable reports the last few days, but I set up a rule in Outlook to handle specific ones according to this criteria:
From Mail Delivery System
and sent to <return-path>
and with "forward this email to firstname.lastname@example.org" in the body
forward it to email@example.com
In 3 days that rule forwarded 135 messages.
Today, in received several messages in response to the last batch of them that said:
This issue appears to have been resolved. Please try resending your message and if you experience a problem reply to this message with the current non-delivery report.
Chief Security Organization
So, perhaps this can help the rest of you out by copying the auto-response rule I used?
11-05-2018 10:26 AM
I have the same problem and it has been 4 days now with no resolution. AT&T and our customers are not getting important emails!
We are a communication website for schools and parents don't get their emails (just at&t domains). We are doing the same thing for 10 years and been blocked once many years ago. Back then, it took less than 48 hours to resolve but now I already sent two emails to the abuse-rbl address with no resolution.
Is there anything else we can do? Should we recommend people to switch email provider?
Any help would be appreciated,
11-10-2018 12:24 PM
I have sent several emails over the course of two months about my server to firstname.lastname@example.org. No change.
Based on the other replies as well over the course of years, it is time to fire the people responding to this email address.
The only solution is to find more public ways to embarrass ATT into acting on my issue and fixing that group.
I think it is time also for me to stop being an ATT customer.
11-26-2018 6:47 AM
I have had the same problem and for two weeks have been emailing the email@example.com and still have not been removed.
Reason: Remote host said: 553 5.3.0 alph163 DNSBL:ATTRBL 521< 126.96.36.199
>_is_blocked.For assistance forward this email to
11-27-2018 1:42 PM
Hi John, I tried sending you a PM, but it's saying your account doesn't allow private messages.
We have the same issue as other people on this forum. When we send email to any account at att.net, sbcglobal.net, or bellsouth.net, the emails are being blocked with the following error message:
553 5.3.0 alph155 DNSBL:RBL 521<ip_address>_is_blocked. For assistance forward this email to firstname.lastname@example.org (in reply to MAIL FROM command))
Both of our IPs are associated with our domain via a reverse DNS lookup, and I've checked both IPs on https://www.dnsbl.info/ and verified that neither appears on any black list.
Would you be able to help if I sent you the IP address info?
11-29-2018 6:29 PM
We’re also receiving the error on my personal email server. All attempts to email the address in the block message are rejected. Really?!
Please unblock us:
alph158 DNSBL:RBL 521< 188.8.131.52 >_is_blocked.For assistance forward this email to email@example.com
12-09-2018 2:52 PM
You are blocking people in my boyscout troop email list. I have sent 4 emails asking to be unblocked - nothing. We are a small group of people that are the only ones who use this IP address. There is no reason to block it. I can see from the thread above this is a futile attempt here - but I gotta try - so here is our plea for help:
PLEASE UNBLOCK OUR IP!
Dec 9 22:38:20 mail postfix/smtp: 0742F7AD0A: to=<firstname.lastname@example.org>, relay=al-ip4-mx-vip2.prodigy.net[184.108.40.206]:25, delay=2, delays=0.04/0.02/1.8/0.07, dsn=5.3.0, status=bounced (host al-ip4-mx-vip2.prodigy.net[220.127.116.11] said: 553 5.3.0 alph158 DNSBL:ATTRBL 521< 18.104.22.168 >_is_blocked.For assistance forward this email to email@example.com (in reply to MAIL FROM command))
12-20-2018 2:38 PM
PLEASE UNBLOCK OUR IP's!
We have sent multiple inquiries over multiple days and have yet to hear anything or have the IPs unblocked.
Our customers are missing important transactional emails.
12-30-2018 6:42 AM
im getting the same thing
ATT is so arrogant they want me to pay to get this resolved
553 5.3.0 flpd576 DNSBL:RBL 521< 22.214.171.124 >_is_blocked.For assistance forward this email to firstname.lastname@example.org
this is due to some Brazilian RBL that places everyone on their list ant then demands payment to be removed
ATT please whitelist 126.96.36.199..I have forwarded this email 30 times to email@example.com
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