For the past several weeks we've noticed a growing problem in delivering mail to yahoo.com email addresses. On all of our servers, at any time of day or night, the mail queues going to yahoo.com are backlogged. It seems Yahoo! has taken the extreme step of "greylisting" all inbound mail in order to avoid spam. They are basically slowing down the rate at which they accept mail, and throwing up error messages telling our server to try again later. Our servers then have to wait some prescribed amount of time before trying to send their queued mail. In the meantime more mail queues up for delivery. When the prescribed time arrives, our server tries again, and is able to deliver a small portion of the queue, when yahoo.com's mail servers once again call a halt and ask to retry later. In the meantime even more mail queues up for delivery to yahoo.com.

lather, rinse, repeat.

This means that at any given moment there are hundreds, if not thousands of mails queued on our servers for yahoo.com, and they aren't willing to take them at a good enough rate to relieve the backlog. It is like a short-cycling stop light at rush hour, except here rush hour never ends.

To add injury to insult, they are being very critical of message contents. many of our customers have reported large numbers of mails being returned as undeliverable with error messages such as:

message text rejected by mx1.mail.yahoo.com: 451

We have no idea what criteria yahoo.com is using to determine what text they are rejecting. The messages we've had forwarded to us looked very "un-spammy"... no styled text, no HTML, no mentions of investment advice or pharmaceutical life enhancements. We're as confused and helpless as you are.

Yahoo.com has no human beings we can talk to in order to resolve this issue, unlike most ISPs. As an autonomous network operator, we often can pick up the phone and call other ISPs and network providers and ask to talk to the people who run mail ops, and actually talk to them. We realize that might be an odd concept in this highly networked and automated world, but it still holds true. We attend technical conferences and meet with our peers, and exchange business cards. We help each other out when bad things happen. We make friends and call in favors. In most cases, if there is a problem between two networks, you can find the person on the other side who can work with us to fix it.

Except with Yahoo.

They are seemingly impenetrable, at least with regards to mail operations. They have some web forms to fill out and hopefully start the process (we can completely understand their desire to hide from user-level support issues since they make no revenue from those users, but they shouldn't hide from network peers!) but the web forms go nowhere and apparently don't do anything.

We're not alone in this. Others have the same problem. While it is a bit comforting to know that we aren't being singled out for poor treatment, it does nothing to help the mail get moving again.

As yahoo!mail is a free service, it is a classic case of "getting what they are paying for."

If you are a digital.forest client and you are FORWARDING your mail to a yahoo.com account, we strongly suggest that you stop doing that - many of you do, which is only adding to the problem. You are likely not getting your mail at all, or if you are, it is VERY late. We suggest you configure your mail client to check your mail directly on our servers. We support POP, IMAP, and webmail. Our servers have a very configurable webmail that you will probably like just as much, if not more than Yahoo's.

If you are a digital.forest client and you are trying to send mail to an address in yahoo.com, we suggest that you contact those people another way, and get an alternative email from them, as the same situation applies, they are not getting your mail, or at the least not in a timely fashion.

If you are a digital.forest client and you maintain mailing lists for communicating with your customers, we strongly suggest that you make every effort to keep those lists "clean" and remove addresses that bounce or cause problems like this. If you are mailing to non-existing addresses then you are clogging mail queues with useless, time-consuming items that only serve to create or enlarge an existing problem.

We'll keep an eye on this, but we suspect it won't be getting better anytime soon. If it does, we'll update this site. Thanks for your patience.

--Chuck Goolsbee
V.P., Technical Operations
digital.forest