Jody asks “Are ‘prefetch opens’ and ‘proxy opens’ the same thing?” Non-human opens An “open” is just someone (or something) fetching a remote image. A non-human-interaction (NHI) open is where some sort of automation fetches the image without human interaction – i.e. it’s fetched when the automation feels like it, not triggered by a user...
Sendy and one-click unsubscribe
If you’re using sendy and you’ve found that RFC 8058 one click unsubscribe fails – or, worse, seems to work but doesn’t actually unsubscribe the user – you should take a look at James’ workaround.
Sending domains and hostnames
Lots of times I see someone asking a question and they talk about their sending domain. And it’s sometimes not 100% clear which domain they mean by that – and when we’re talking about alignment and reputation it can make a difference. So here’s a list of (some of?) the different places a mailserver uses a domain. Hostnames Machine Hostname: What the operating system...
If you’re using Entrust for your BIMI VMC …
BIMI is the protocol you can use to publish an icon to display in the inbox of some large consumer webmail providers. To have it displayed at Gmail you need more than just clean DMARC and a published BIMI record, you also need to have a Verified Mark Certificate, a VMC. A VMC is a certificate, very similar in many ways to the TLS certificates used to secure webpages. It’s issued by a...
DMARC: The good, the bad and the ugly
DMARC is the newest of the authentication protocols. It compares the domain in the From: address to the domains authenticated by SPF and DKIM. If either SPF or DKIM pass and they are in the same organizational domain as the domain in the From: address then the email is authenticated with DMARC. I wrote A Brief DMARC primer back in 2014 – when Yahoo deployed p=reject late on a Friday and...
Who’s your Email Czar?
The gentleman with the excellent hat is Иван IV Васильевич, The Great Sovereign, Tsar and Grand Prince of all Russia, Vladimir, Moscow, Novgorod, Tsar of Kazan, Tsar of Astrakhan, Sovereign of Pskov, Grand Prince of Smolensk, Tver, Yugorsk, Perm, Vyatka, Bolgar and others, Sovereign and Grand Prince of Novgorod of the Lower Land, Chernigov, Ryazan, Polotsk, Rostov, Yaroslavl, Beloozero, Livonia...
Why Deliverability Depends
A common complaint about the advice or answers any deliverability person gives is that the generic answer to questions is: It Depends. This is frustrating for a lot of folks because they think they’re asking a simple question and so, clearly, there should be one, simple, clear answer. The problem is that there is almost never one answer in deliverability and details do matter. Let’s...
Deliveries and Opens and Clicks
I always want to say “Emails, and Opens, and Clicks… Oh My!” when I’m talking about them. We really want to understand how a mailbox provider perceives the streams of email we send them. Some of the things the provider looks at are technical and objective – is the email coming from who it claims to be coming from? Is there an attachment that contains a virus? We have...
Warmup is Communication
A still from Cargo Cult, by Bastien Dubois During the war they saw airplanes land with lots of good materials, and they want the same thing to happen now. So they’ve arranged to make things like runways, to put fires along the sides of the runways, to make a wooden hut for a man to sit in, with two wooden pieces on his head like headphones and bars of bamboo sticking out like...
Filter Evasion
It’s deliverability week, so everyone is talking about deliverability. But I’d like to take a moment to mention deliverability’s evil twin from the mirror universe – filter evasion. The goal of filter evasion seems at first sight very similar to that of deliverability – put the email in the inbox – but the two practices start from very different places...