Mail problems at AOL


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Over the last few months there have been ongoing mail problems at AOL. These problems are all over the map and are resulting in a lot of delayed and unsent email. People are reporting a number of different error messages from AOL mail servers. These messages don’t seem to always be accurate or correct.
A couple examples:
SMTP error from remote mail server after end of data: host []: 521 5.2.1 :(CON:B1) reported by the owner of a low volume discussion list with paying subscribers that should have zero complaints.
delivery temporarily suspended: host[] refused to talk to me: 421 Service unavailable – try again later reported by all sorts of senders. failed after I sent the message. Remote host said: 521 5.2.1 “TempFail” reported by a small mail host.
554 ESMTP not accepting connections reported by an ESP.
421 4.7.0 Error: too many errors reported by a university, a mailserver vendor and a bunch of ISP and telcos.
This is not a constant or consistent set of errors. It is coming and going, with AOL reporting things are fixed and senders reporting queues emptying. However, every time it seems to be fixed, something else breaks.
There isn’t much anyone outside of AOL can do, though. This has to be fixed internally by their engineers. I’m afraid this is just the result of a highly complex system that is failing due to bit rot, though. Which means only significant investment in time and programming power can fix this for all of us. I do hope I’m wrong.
It’s weird to be writing this blog post the same day I found out that Jay Levitt, one of the original AOL mail system architects has died. I didn’t know Jay well, although he did post a comment here once or twice. I haven’t heard any details, yet, but it’s strange to be writing about AOL mail today.
Update Feb 8, 2016: AOL users are having problems logging in. Word to the Wise cannot help you. Please do not contact us for help. Contact AOL directly.

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  • The specific issue you quote was due to a new anti spam rule last week and has been rolled back since. There shouldn’t be any issues going on over the last few months. If you are aware of anything else, don’t hesitate and contact me directly.

  • I’ve been hearing about AOL problems for months, and I know that a number of people have been in contact with AOL and been providing evidence of the problems. People have been seeing problems with delivery to AOL since at least August: There was also a round of problems back in May:
    While the underlying reasons for the problems may be different, a lot of people are struggling to deliver real mail to AOL over the last few months.

  • 32,088 messages in the queue while getting:
    2012-10-15 13:46:10 SMTP service unavailable: “421 4.2.1 “Service unavailable. Please try again later.”” received from ( while connected from ( to (
    This is the same thing that happened to us during the other dates Laura mentions.

  • I wish they could even get their error messages straight:
    —– The following addresses had permanent fatal errors —–
    (reason: 521 5.2.1 “TempFail”)
    So is it a “TempFail” and will continue to try to deliver it, or is it a “permanent fatal error”???

  • this has been going on all year that I have not been getting some e-mails… I sent myself to my aol account an e-mail from my gmail two hrs ago and have still not gotten it… I have been
    with aol since the 90s and people have been telling me to move… maybe I should because
    I can’t do business this way…

  • EXACTLY what Martin said. I’ve been with AOL since 1995 or so. But I can’t stand it when people ask me about emails they sent hours ago that I haven’t received.

  • I am having the same issue. Yesterday, it took about 7 hours for me to finally receive my emails….and they were of an important nature. What is going on with AOL? I have been with AOL forever and all of my clients have my AOL email address which is my reason for staying with AOL (even though I have Comcast service at my home and a Comcast email address).

  • I have also noticed a heavy impact on our email campaigns performance lately. A heavy percentage of valid confirmed opt-in contacts are soft-bouncing:
    Delivery temporarily suspended: host[] refused to talk to me: 421 Service unavailable – try again later–
    Even though we are part of the feedback loop, and are on their whitelist, the delivery rate has dropped significantly. I hope AOL can address this soon!

  • Here is one I just saw on Wednesday trying to email my attorney critical documents. I received the test email from them just fine. When I replied to that email, I got:
    Unexpected connection response from server:
    421 Service unavailable – try again later
    This is not the first time I have had problems trying to email him.

  • I’m quite concerned. I have experienced the following:
    Important mail being bounced back to the sender
    Some mail never arriving
    Mails I have seen and opened, vanishing
    Not being able to find things when using accurate search terms -eg word “Jane” in search term – doesn’t find it, but I find it after manual search
    Very poor spellcheck suggestions and sometimes none where there should be one

  • Yeah ,I wrote a mail to a guy who’s got an ‘aol’ adress.
    I received an error message (I use an ‘’ adress).
    Does the problem come from aol?

  • AOL mail has been a nightmare for 3 – 4 days now
    “technical problem”, again and again.
    using Google Chrome seems to aggravate it.
    IE has less problems.
    (Axoul, no; you just have an old address or the person is a spammer)

  • Can I join the band of folk complaining about AOL. I am finding people not able to send to it or very long delays in me receiving replies that had been sent… and it am paying for AOL

  • As of yesterday, EVERYTHING send from my aol account goes into my friends & coworkers SPAM folders, or is not delivered at all!
    Some co-workers tell me that the emails are missing a “Signed by MX.AOL.COM” signature…
    What does that mean &/or how can I change it.

  • Hello
    I know where some of ur msg are going and that is to my email inbox. I can not open them, but they r all AOL.
    I want this stopped
    This started about 5 days ago and as I delete 12 msg, I get 12 back. I think if I kept deleting I would get flooded with msg.
    I dont have any connections with AOL
    I too am frustrated,
    What can I do?

  • Verifying if there are still issues. We are unable to send to an AOL account – receiving the error message: ( ESMTP not accepting connections)
    This thread is from 2012….is this seriously still an issue?

  • Hey @Andrew,
    I am having the same problem:

    Action: delayed
    Status: 4.0.0
    Remote-MTA: dns;
    Diagnostic-Code: smtp; 554 ESMTP not accepting connections

    I was shocked to find this thread and even more so that it is from 2012.

  • Good Evening
    AOL emails for some reason get marked as “FAILED” with the following message:
    IPADDR failed after I sent the message./Remote host said: 521 5.2.1 : AOL will not accept delivery of this message./
    We are email marketing firm and we do not send SPAM.
    I contacted customer care and submitted numerous forms – but no response and we are still facing the same daily.
    Any advice?
    Thank you very much
    Andrew Homsky

  • That’s not a full AOL bounce message, so the first step is to get the full rejection message from AOL. Once you have that, it will give you an idea if it’s a content problem or an IP reputation problem or something else. Once you know what is triggering the filter, then you can modify your processes.

  • AOL made all their money in the early 1990’s charging by the minute. While they wait for another company to buy them out the service gets worse and worse. Every other email I try to send gives me an error message. It just started within the last two weeks. Do they go directly to NSA first before I am allowed to send them?

  • Still issues at AOL. I wish my customers didn’t have their email accounts with AOL! Such a headache!
    SMTP error from remote mail server after initial connection:
    host []: 554 ESMTP not accepting connections

  • I am so upset……it has been months since I have been able to send emails out from my aol account. When I call aol to advise them of my problem they try to sell me something. When I try to send a message out I get: Technical issues encountered or something to that effect. Does anyone know how to resolve this ????? If so ……respond to Thanks

  • Hello Laura,
    Please can advise. We see alot of these AOL errors
    SMTP service unavailable: “421 Service unavailable – try again later” received from ( while connected from ( to (
    SMTP service unavailable: “421 4.7.1 : (DYN:T1)” received from ( while connected from ( to (
    I’ve sent a couple of messages to AOL requesting for help. As always, nothing has been done.
    Can Laura or any one here help please?

  • If that’s a mail server that you use, then there’s some bad mail going through it that is triggering AOL’s filters. Right now, these are temporary blocks but if there is no improvement in your mail, then it’s likely that you will see more permanent blocks and worse delivery over time.
    We can help you identify the underlying cause of your issues and provide consulting to resolve them. Feel free to contact us by phone or our contact address for more information.

  • Received this at 7:30 am when I sent an email at 11:10pm to a client at their aol address.
    delivery temporarily suspended: host[] refused to talk to me: 421 4.7.1 :
    so from your blog I am happy to understand this isnt a spam report but this does not help sending information to my client.
    Post here date back to 2012…. this is upsetting that a tech company cant fix these issues in a reliable amount of time.
    I would love to hear if anyone has feedback on the status of improvement or resolve so I can make other “delivery” choices when I see an aol email.

  • My problem is different. My AOL mail buttons do not work, the header of the mail is missing, I do have a garbage symbol at the end of my messages so I am able to delete the message from there. When I go to the deleted messages, I have to delete them individually. It is all messed up. Can anyone help?
    Thanks shirley

  • Over last three weeks I have been having trouble signing in to my aol site site very slow to respond. I discovered that when I had changed companies and first signed onto my AOL account it asked for a recovery web site. I chose my new company email but did not do the recovery access code for several days and it expired. When I reintiated the recovery email mail access the problem went away. So i would assume its a security measure hope this helps other users. Long time AOL user

  • After getting properly coded bounce messages, which could be solved with the bounce codes and links provided, now I am getting this:
    SMTP error from remote mail server after initial connection:
    host []: 554 ESMTP not accepting connections
    Can anybody explain me how to solve these errors? Or better, what AOL is going to do to solve these errors?

  • SMTP error from remote mail server after end of data:
    521 5.2.1 : AOL will not accept delivery of this message.
    This has been ongoing for several days. Since all of our web sites are connected to the same email server, we are unable to send email from any of our web sites to aol users. We checked our ip reputation and it came back as good with aol and is not blacklisted. Likewise all of our email lists which we do not send very often comply with can spam and are double optin. We also permanently blacklist any user who unsubscribes so they can never sign up with the same email address.

  • Hi, Mike,
    I’ll do a longer post on this because I think it’s interesting but given the block is coming after data, this is a content not an IP block. I’d look hard at the URLs and links in the messages.

  • host []
    SMTP error from remote mail server after end of data:
    521 5.2.1 : AOL will not accept delivery of this message.
    have corresponded to the same aol clients for years. began getting returned emails around Nov 10 or so. no other changes. evidently lots of other people with same issue. all my settings are correct and all other functions are operational. please fix.

  • DEFAULT Report ID: webprd-a100-20160208-193412
    the error message just started today…it takes me 20 to 30 tries (logins) to get to my mail. If I leave the webpage (do not logout) I have to start the whole process over again.

  • the error message (above post) also occurs when logging into the site… very frustrating… any help appreciated.

  • Over the last month a cartoon like cloud appears with the caption “hmmmm we can’t deliver your message” My business and consequently my income is in jeopardy. What’s up with AOL? When I check my mailbox, it’s listed as “sent” but no one is getting the messages.

  • I just setup a mail server (postfix) for the first time on my forum’s VPS. Wow! what a can of worms I got myself into!. The first problem was with addresses, but fortunately I found a website to report the issue and Microsoft or whoever was very responsive and fixed the problem within a few hours.
    Is there not a similar site for AOL?

  • I’ve a client who has been trying to send me an email over a dozen times now and she keeps getting this message back from my aol server… any ideas? thanks
    “This message was created automatically by mail delivery software.
    A message that you sent has not yet been delivered to one or more of its
    recipients after more than 48 hours on the queue on
    The message identifier is: 1atcuc-0004k1-Hj
    The subject of the message is: Fwd: Email signature
    The date of the message is: Fri, 22 Apr 2016 16:22:30 +0100
    The address to which the message has not yet been delivered is:
    Delay reason: SMTP error from remote mail server after initial connection:
    host []: 421 Service unavailable – try again later
    No action is required on your part. Delivery attempts will continue for
    some time, and this warning may be repeated at intervals if the message
    remains undelivered. Eventually the mail delivery software will give up,
    and when that happens, the message will be returned to you.”

  • Not to mention the constant “Not responding,” “Temporarily unable to send or list mail,” and a host of others. Idiotic and you would think AOL would get on the stick and fix these issues rather than make soothing noises every time you call for them to fix a problem. Ludicrous.

  • We have just had all our mail to AOL based club members blocked by AOL. Not good when you are a flying club sending out important safety information to your members! My advice to our members is simple, get yourself a new mail account somewhere else the does work…… I wrote to AOL, guess what – no reply.

  • Here we are in 2016 four years after this became publicly known issue and our company still can’t send email to our customers who use an AOL email address. We sent out an email to 80 of our clients a couple days ago and only the recipients who use an AOL address did not receive the message. All other major providers like Gmail and Yahoo and Comcast received the message. But AOL users did not and the messages to them are stuck in our mail server with delivery logs that look like this:
    2016-10-10 12:34:40 1flUYa-0306Rs-Mo []: SMTP error from remote mail server after initial connection: 421 Service unavailable – try again later
    2016-10-10 12:34:40 1flUYa-0306Rs-Mo []: SMTP error from remote mail server after initial connection: 451 4.3.2 Internal server error
    2016-10-10 12:34:46 1flUYa-0306Rs-Mo SMTP error from remote mail server after end of data: 421 4.2.1 “Service unavailable. Please try again later.”
    2016-10-10 12:34:46 1flUYa-0306Rs-Mo == R=lookuphost T=remote_smtp defer (-46) []: SMTP error from remote mail server after end of data: 421 4.2.1 “Service unavailable. Please try again later.”
    Naturally I removed the AOL user’s real name and any sensitive info but as you can see AOL just won’t accept messages from our company email to our clients who use AOL.
    I know the real solution is to get people to switch away from AOL to a service that actually works but try telling that to a die-hard AOL user and they’ll just get upset.
    Our solution is we’re just going to put a notice up on our web site telling users that if they have an AOL email address they won’t receive their order updates and other correspondence from purchases on our web site because AOL mail servers don’t work right. Heck we’ll probably post a link to this page so they can see for themselves the problem is not on our end.
    Trying to speak to AOL about it is like talking to a brick wall.

  • This article has been written on 2012 and it’s now December 2016 but the error messages that we receive are exactly the same.

  • Most of the problems is with free AOL … I also have been an AOL member since it first started in Texas. Problems then were minor or minimal. I switch over to free AOL after many years and that’s when I started have all of the AOL problems. I think they just want free members to become paying customers, that’s why you can’t get any help or satisfaction. Pay for the service and I bet many problems will go away.

  • I am on a mailing list maintained by an AOL user and I get all the stuff he sends out, but if I try to reply to any of it AOL blocks my replies. I am going to have to try and find his phone number. It is very frustrating. AOL should be aware that it is not just their own customers who are inconvenienced by these bugs.

    SMTP error from remote mail server after end of data
    WTH is wrong W/AOL ??

  • This is a fascinating thread, extending from October 2012 to October 2017 — amazing, how long it takes for .Aol to get its servers configured correctly.
    I have found a work-around, at least for individual, personal messages, to get through to .Aol subscribers:
    Send from a client that provides _Delivery Status Notification_ (DSN). DSN may be a feature on some stand-alone clients, but I am using it with the _Yandex_ web-mail client. The _Notify Me_ button, directly below the text-entry box, activates this feature.
    The Yandex client may be configured to send a ‘chime tone’ through your system’s loudspeakers when the target SMTP server accepts the transmission. They also send a _Confirmation of Delivery_ text message into the sender’s Inbox.
    When sending to .Aol, simply wait for the ‘chime’. ‘Normal’ servers (GMail is well-behaved, among others) ‘ring the chime’ about two or five seconds after hitting the ‘Send’ button.
    On its ‘good days’ .Aol will sound the chime within at least 15-20 seconds. On its ‘bad days’ the chime will be heard after several hours — or, up to a day later, on its ‘very bad days’.
    On its ‘very-very worst days’ the chime will never ring, and after about four days the ‘.Aol Postmaster’ will produce a non-delivery message, for a variety of reasons. The original message is then returned to the sender as an attached .eml file.
    How to handle this depends upon the urgency of the communication. For casual communication, wait to see what happens.
    For urgent communication, I give .Aol five minutes to acknowledge the first message, and then begin sending multiple copies (use _Reply_ to keep the sender’s address constant) in rapid-fire fashion. Usually, sooner or later, you’ll hear the acknowledgement signal, and then you can stop.
    When sending to .Aol subscribers I now append a Roman numeral (e.g., I, II, III, IV, etc.) to the Subject line. Copies after the first have a header to the recipient’s attention explaining I have no idea which copy will get through, so they should disregard all but one of a series having the same Subject line.
    Example: .Aol was recently having a ‘bad few days’ so the same message was sent as ‘Subject Line’ with Roman numerals I through VII, in rapid-fire succession. Message VI ‘rang the chime’ in a few minutes, and produced a text notification of successful delivery. Message VII had already gone out when the ‘chime’ sounded, but I knew I could then stop sending.
    Experience has shown that at least one message will eventually get through.
    In the example above, messages I through V and VII all failed to sound the ‘chime’ and after some days were returned to my Inbox as .eml attachments, with varying error codes indicating non-delivery.
    However, message VI was successfully received by the addressee.
    This works with .Aol servers. Some others (iCloud, for one) routinely ignore all requests for Delivery Status. Delivery must be confirmed by phone or snail-mail.

  • Hmmm … after re-reading this thread, I see it’s not just personal email, but also some businesses that have a serious problem with reaching their clients who subscribe to .Aol.
    It’s possible the routine I use, manually, could be automated with client that accepts scripting, for businesses with a mailing list.

  • Still an issue as of December 29th, 2017.
    Replying from gmail to someone on AOL brings:
    554 5.7.1 : (RLY:B1)
    Expanding the part in parentheses on the linked error codes page (but it doesn’t work without javascript?!) I get:
    “This error message is created by a dynamic block placed on an IP address by our system. Dynamic blocks are placed when the IP’s statistics break our threshold. These are automated blocks that are removed by the system within 24 hours once the complaints are again below the threshold.”
    Yeah, right. AOL blocks mail from Google? Tried again with less of the original message quoted and it didn’t come back.
    When AOL fights with Google which one does that make look bad?
    I forgot about Delivery Status Notifications and Read Receipts. I remember being annoyed by them in 1990 as the receipt messages clogged my inbox and again in 2005 as Outlook Express would pop up dialog boxes on opening some messages asking if I was okay with sending the ACKs.

  • Wow, I had resolved those problems some time back—once or twice asked a Web weaver to send a request to AOL to whitelist a domain, which was done, resolving the issue for many people who were probably unaware, but today I have what should be a simple, unrelated issue, an error message saying “There was a problem sending the message. Please try again later.”
    I thought maybe it was because I was forwarding an e-mail, so I copied and pasted, and got virtually the same message when trying to save: “There was a problem saving the message. Please try again later.”
    No clue as to what may be the issue. Thoughts welcome! (AOL member since the 1990s, like others here. Every time it gets really bad and I think of leaving, they manage to resolve the issue and I stay.)

By laura

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