Does email have a guarantee of delivery?

A client asked me earlier this week what SLAs ISPs provided for email delivery. The short answer is that there isn’t a SLA and that the only guarantee is that the email will get there when it gets there.
But as I was mentioning this to Steve, he pointed out that there was a recent change in the RFCs for email. In both RFC 821/2 and RFC 2821/2 (the original email related RFCs and the update in the early 2000’s) the RFCs stated that once a receiving MTA accepted an email that that MTA was required to either delivery the mail or generate an asynchronous bounce. While this isn’t a standard SLA, it does mean that a 2xy response after DATA meant the email would either be delivered to the user or be sent back to the sender. Despite the RFC requirements some receivers would still drop mail on the floor for various reasons, sometimes intentionally and sometimes not.
RFC 5321/2, the current SMTP standard, still says that once a server accepts the mail it must not lose that mail ‘for frivolous reasons.’ The RFC goes on to admit, though, that in recent years, SMTP servers are under a range of attacks and dropping mail on the floor is not frivolous in those cases.
 

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Delivery emergencies and the holidays

There is a lot of contention between ISPs and senders at the best of times. As we move into the holiday season, retailers are increasing their email marketing, sometimes quite significantly. This causes more delivery issues as recipients and MTAs react to the increased volume.
At many non retail companies, however, the pace of work slows down. There are distractions and office parties and people taking long lunches to finish their holiday shopping. Non-critical departments are not staffed for official holidays like Thanksgiving and Christmas Day.
This means that delivery issues may not be responded to as quickly as senders might like. Just this morning I got a call from someone who wants his delivery issues to be fixed by tomorrow. I’m sorry, even if I were to treat this as an emergency, there is work and investigation that needs to be done at the ISP end, and they’re not necessarily going to have a staffed delivery desk on Thanksgiving day. And even if they do have a staffed desk, it’s possible the staff won’t be focused and issues won’t be handled as fast as they might otherwise be.
I’d love to help, but there’s a limit to what I can do. Filtering decisions are made by the ISP, or their filter vendor, and sometimes they don’t happen as fast as we’d like. It’s frustrating for senders to have to deal with, but these are the realities of email delivery.

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Emails that make you smile

This summer’s non-work project for me has been training for a 5K run with Fleet Feet in Menlo Park. As part of the training programs we get weekly emails from the store on Monday. As I was reading through today’s email, I found myself smiling and happy. Lisa, who is one of the store owners and writes the emails, is just so happy and bouncy and thrilled to share her love of running and that comes through in the newsletter.
Our group’s primary coach is the other store owner. During runs we often talk about random stuff, and when I tell people I do email delivery, they always start talking about their experience with email and spam. One night I was running with Jim, and we were talking about Jim’s experiences with sending email. He mentioned their ESP and talked about how convenient it was. But then he mentioned he wasn’t sure that they were sending enough mail (which made me laugh hard enough I almost tripped on a curb).
I realized I am not just a delivery expert when I started thinking about all the ways they could increase the amount of email they send, while still maintaining the quality and the friendly feel of their bulk emails. What could they offer local runners that would increase the value of the store to them? The first very obvious thing was a race calendar. There are dozens of local races every week, telling folks about upcoming races and entry deadlines would be a way to contact folks regularly without it always being a “buy stuff from us!!”
What commercial emails have you gotten recently that have made you smile?

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8 things that make your mail look like spam

In the comments of last week’s Wednesday question John B. asked

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