20% of email doesn't make it to the inbox

Return Path released their global delivery report for the second half of 2009. To put together the report, they look at mail delivery to the Mailbox Monitor accounts at 131 different ISPs for 600,000+ sends. In the US, 20% of the email sent by Mailbox Monitor customers to Return Path seed accounts doesn’t make it to the inbox. In fact, 16% of the email just disappears.
I’ve blogged in the past about previous Return Path deliverability studies. The recommendations and comments in those previous posts still apply. Senders must pay attention to engagement, permission, complaints and other policy issues. But none of those things really explain why email is missing.
Why is so much mail disappearing? It doesn’t match with the philosophy of the ISPs. Most ISPs do their best to deliver email that they accept and I don’t really expect that ISPs are starting to hard block so many Return Path customers in the middle of a send. The real clue came looking at the Yahoo numbers. Yahoo is one of those ISPs that does not delete mail they have accepted, but does slow down senders. Other ISPs are following Yahoo’s lead and using temporary failures as a way to regulate and limit email sent by senders with poor to inadequate reputations. They aren’t blocking the senders outright, but they are issuing lots of 4xx “come back later” messages.
What is supposed to happen when an ISP issues a 4xx message during the SMTP transaction is that email should be queued and retried. Modern bulk MTAs (MessageSystems, Port25, Strongmail) allow senders to fine tune bounce handling, and designate how many times an email is retried, even allowing no retries on a temporary failure.
What if the missing mail is a result of senders aggressively handling 4xx messages? Some of the companies I’ve consulted for delete email addresses from mailing lists after 2 or 3 4xx responses. Other companies only retry for 12 – 24 hours and then the email is treated as hard bounced.
Return Path is reporting this as a delivery failure, and the tone of discussion I’m seeing seems to be blaming ISPs for overly aggressive spamfiltering. I don’t really think it’s entirely an ISP problem, though. I think it is indicative of poor practices on the part of senders. Not just the obvious permission and engagement issues that many senders deal with, but also poor policy on handling bounces. Perhaps the policy is fine, but the implementation doesn’t reflect the stated policy. Maybe they’re relying on defaults from their MTA vendor.
In any case, this is yet another example of how senders are in control of their delivery problems. Better bounce handling for temporary failures would lower the amount of email that never makes it to the ISP. This isn’t sufficient for 100% inbox placement, but if the email is never handed off to the ISP it is impossible for that email to make it to the inbox.

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E-Postage Just Won't Die

E-Postage is back! Wired covers a report from New Scientist. Here’s what they have to say: “Yahoo’s researchers want you to voluntarily slap a one-cent stamp on your outgoing e-mails, with proceeds going to charity, in a bid to cut down on spam. Can doing good really do away with spam, which consumes 33 terawatt hours of electricity every year, not to mention way too much of our time?”
Alex Rubin at Return Path says hold up, wait a minute. He writes: “Our contacts at Yahoo! tell us this idea is purely in the research realm, and is not scheduled for development in Yahoo! Mail. In other words: it isn’t even vaporware and isn’t likely to be a part of the Yahoo! mail system anytime soon.” He goes on to say (I’m paraphrasing) that oops, Yahoo didn’t really intend for this research to become public.
So, apparently, there are no plans for Yahoo to roll out E-Postage today, tomorrow or next week. Nothing to see here, beyond a simple web site and some thoughts from a Yahoo researcher. Some individual’s hopeful vision for the future, not a corporate announcement of an upcoming product.
E-Postage has always been a neat idea, I’ve thought. A neat idea beset by insurmountable problems. First, end users don’t want to pay for the email messages they send, they want all you can eat. With years of webmail providers offering free email access, you’ll have a heck of a time convincing somebody’s grandmother that they have to pony up a nickel to be able to email the grandkids.
Then, answer me this: Who’s going to handle the economics on the back-end? And any time you have a computer storing a resource (like, say, account information for that tiny little bit of money you’ll need to be able to send me an email), that information can be hacked, exploited, stolen. You think spammers are actually going to pony up? Why would they? They’ll just hack into millions of exploitable computers, stealing five cents from everyone along the way, and gleefully shoveling millions of spams into millions of inboxes.
This concept of E-Postage, either paying money to send email, or spending “computational power” to send email, has been kicking around for years. Periodically, some researcher comes up with the idea anew, and suggests that we all immediately adopt their sure fire plan to solve the world’s spam problem, immediately, pennies at a time. These ideas never seem to go anywhere. And that will never change until somebody can actually convince most of the world to adopt their proposed scheme. Will it ever happen? Never say never, but I have no plans to rush out and buy e-Stamps any time soon.
— Al Iverson

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Failed delivery of permission based email

A few weeks ago, ReturnPath published a study showing that 20% of permission based email was blocked. I previously discussed the definition of permission based email and that not all the mail described as permission based is actually sent with the permission of the recipient. However, I only consider this a small fraction of the mail RP is measuring, somewhere in the 3 – 5% range. What happens with the other 17 – 15% of that mail? Why is it being blocked?
There are 3 primary things I see that cause asked for and wanted email to be blocked.

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Rescuing reputation

One of the more challenging things I do is work with companies who have poor reputations that they’re trying to repair. These companies have been getting by with poor practices for a while, but finally the daily delivery falls below their pain threshold and they decide they need to fix things.
That’s when they call me in, usually asking me if I can go to the ISPs and tell the ISPs that they’re not spammers, they’re doing everything right and will the ISP please stop unfairly blocking them. Usually I will agree to talk to the ISPs, if fixing the underlying problems doesn’t improve their delivery on its own. But before we can talk to the ISPs, we have to try to fix things and at least have some visible changes in behavior to take to them. Once they have externally visible changes, then we can ask the ISPs for a little slack.
With these clients there isn’t just one thing they’ve done to create their bad reputation. Often nothing they’re doing is really evil, it’s just a combination of sorta-bad practices that makes their overall reputation really bad. The struggle is fixing the reputation requires more than one change and no single change is going to necessarily make an immediate improvement on their reputation.
This is a struggle for the customer, because they have to start thinking about email differently. Things have to be done differently from how they’ve always been done. This is a struggle for me because I can’t guarantee if they do this one thing that it will have improved delivery. I can’t guarantee that any one thing will fix their delivery, because ISPs measure and weight dozens of things as part of their delivery making decisions. But what I can guarantee is that if they make the small improvements I recommend then their overall reputation and delivery will improve.
What small improvement have you made today?

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