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 mailin-02.mx.aol.com [64.12.90.65]: 521 5.2.1 :(CON:B1) http://postmaster.info.aol.com/errors/554conb1.html reported by the owner of a low volume discussion list with paying subscribers that should have zero complaints.
delivery temporarily suspended: host mailin-01.mx.aol.com[205.188.146.193] refused to talk to me: 421 mtain-dg03.r1000.mx.aol.com Service unavailable – try again later reported by all sorts of senders.
205.188.190.2 failed after I sent the message. Remote host said: 521 5.2.1 “TempFail” reported by a small mail host.
554 mtain-dc03.r1000.mx.aol.com ESMTP not accepting connections reported by an ESP.
421 4.7.0 mtain-dg05.r1000.mx.aol.com 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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