SPF ?all

The most read post on the blog is Authenticating with SPF: -all or ~all. In fact, it’s in the top 5 posts every single day. We still get comments on it, too. Usually from folks who disagree with my recommendations.
I still stand by my recommendations, though. It doesn’t really matter if you choose ~all or -all in your SPF records. Why? No major provider is rejecting mail solely because of a SPF fail. They may bulk the mail, but they won’t reject it. That’s why, in a deliverability context, it doesn’t matter which one you choose.
My one rule for SPF is never use ?all. Just. No. In the spec, ?all is “testing” mode. But it really is a signifier that the person who put the SPF record together doesn’t know what they’re doing. Unless they really are testing, but even then you shouldn’t see ?all on records for weeks or months.
~ or – never ?

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Ask Laura: Can you help me understand no auth / no entry?

AskLaura_Heading3
Dear Laura,
I’m a little confused by the term “no auth / no entry”. Gmail and other major receivers seem to be moving towards requiring authentication before they’ll even consider delivery.
Does this just mean SPF and DKIM, or does this mean the much more stringent DMARC, as well?
Thanks,
No Shirt, No Shoes, No What Now?

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Check your tech

One of the things we do for just about every new client coming into WttW is have them send us an email from their bulk mail system. We then check it for technical correctness. This includes things like reviewing all the different From headers, rDNS of the connecting IP, List-Unsubscribe headers and authentication. This is always useful, IMO, because we often find things that were right when they were set up, but due to other changes at the customer they’re not 100% correct any more.
This happens to most of us. Even a company as small as Word to the Wise misses a rDNS update here or a hostname change update there when making infrastructure changes. That’s even when the same people know about email and are responsible for the infrastructure.
One of the most common problems we see is a SPF record that has accumulated include: files from previous providers. There are a couple reasons for this. One is the fact that SPF is set up while still at the old provider in anticipation of moving to the new provider. Once the move is made no one goes back to clean up the SPF record and remove the old entries. The other reason is that a lot of tech folks don’t like to delete things. Deleting things can lead to problems, and there’s no harm in a little extra in the SPF record. Except, eventually, there are so many include files that the lookup fails.
Every mailer should schedule a regular tech audit for their mail. Things change and sometimes in the midst of chance we don’t always catch some of the little details.

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