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 is about helping you succeed

I was talking with another delivery person today who’s dealing with a customer struggling with some issues. As most of these discussions go, we get to the part where we have to tell the customer that what they’re doing looks problematic from the outside. And then the customer gets all upset and angry and starts complaining to account reps or managers or executives.
The challenge of delivery is working with clients who don’t want to hear they have to change what they’re doing. Some senders deflect better than a 3 year old caught with her hand in the cookie jar.
I think all of us in the delivery space, or at least most of us, want our customers and clients to succeed in their email goals. We want you to have a great mailing program. But when your delivery is having problems, getting to a great mailing program means doing something differently.
These changes can be hard, both in terms of thinking differently about email and how it works and about business models. Some business models make it extremely difficult to use emails. We understand that. We don’t make the rules, we just explain them.
We want your mail to work.

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Deliverability of Facebook.com email addresses

Christopher Penn at What Counts did some testing to see what delivery to Facebook.com addresses looks like. It looks pretty grim.
 

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Spamhaus answers questions

Lost in all of the DOS attack news this week is that the first installment of Spamhaus answering questions from marketers in Ken Magill’s newsletter.
It’s well worth a read for anyone who is interested in hearing directly from Spamhaus.
One quote stood out for me, and it really sums up how I try to work with clients and their email programs.

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