AOL Updates Spam Filtering

Over on the AOL Postmaster blog, Lili Crowley announced yesterday that AOL has made changes to their spam filtering system. Specifically, more senders may be subject to blocking with CON:B1 errors. AOL’s website explains that CON:B1 errors indicate that an IP address is being  blocked “due to a spike in unfavorable e-mail statistics.” This strongly suggests that a sender blocked with a CON:B1 error message has a negative sending reputation. This is yet another data point as to how ISPs have been tightening up spam filtering and reputation requirements over the past few years. What you might have been able to deliver five years ago, you might not be able to get delivered today.

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AOL Postmaster page hacked

Per Boing Boing: the AOL postmaster page was hacked over the weekend.
As of now the site is restored. But I’m hearing that all the scripts are still down. This means no one can open tickets, sign up for FBLs, apply for whitelisting or check the status of reports. I expect this will be fixed soon, but for now it looks like AOL issues are going to be impossible to resolve.

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AOL improving

I’m hearing from lots of folks that they’re seeing some improvement in delivery to AOL accounts.
As everyone can imagine, the AOL situation has been a common thread of discussion on many delivery lists. One person even commented at how fragile the AOL mail server seems. My own thoughts are a little different. The AOL mail system is notoriously complex and integrated. Many of the folks who built it have been laid off or otherwise moved on to other companies. I know there are still smart, competent people riding herd on the AOL mail servers, but I expect they don’t have the resources to do the ongoing maintenance and the fire fighting and all the other tasks that a mailserver handling billions of emails needs.
What this means is that the AOL mail system has been suffering from bit rot for at least 2 years. It is to the original designers’ credit that it’s taken this long before there were major problems like we’ve seen over the last week.

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AOL delivery problems

There have been ongoing reports this week from ESPs and ISPs that AOL is having problems accepting email. People are reporting difficulties connecting to AOL MTAs and random dropping of connections. Other people are reporting random rejection messages that make no sense. A number of folks are seeing rejections claiming that the reason is a new IP when that IP has successfully sent mail from that IP in the recent past.
AOL seems to be working on things, and some people are seeing improvements. If you’re seeing AOL problems recently, it’s not you. It’s them.
EDIT: AOL has asked senders to please reduce mail volume while they are resolving issues.

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