https://www.wordtothewise.com/index.xmlRecent content on Word to the WiseHugoen-usFri, 13 Mar 2026 14:15:32 +0000https://www.wordtothewise.com/2026/03/upcoming-webinar-on-gmail-and-inbox-signals/Fri, 13 Mar 2026 14:15:32 +0000https://www.wordtothewise.com/2026/03/upcoming-webinar-on-gmail-and-inbox-signals/I’m thrilled to announce I’m sitting down at the beginning of April to talk about inboxing in 2026.https://www.wordtothewise.com/2026/02/recent-writings-and-events/Thu, 19 Feb 2026 14:58:46 +0000https://www.wordtothewise.com/2026/02/recent-writings-and-events/I don’t know about you, but we’re more than 6 weeks into 2026 and I can’t figure out where all the time has gone. It’s been a much busier January than I’m used to. I’ve been working on a lot, including a project I’ve been trying to get off the ground for a while. I’m really excited it’s finally taking shape and I hope to be able to share it with folks in the next month or so.https://www.wordtothewise.com/2026/01/not-business-as-usual/Mon, 26 Jan 2026 14:29:33 +0000https://www.wordtothewise.com/2026/01/not-business-as-usual/I don’t know what to say about what’s happening in the US, but I know I can’t stay silent, either. I don’t have anything inspiring to say here. I just cannot keep silent and pretend it’s all business as usual. I’m saddened, I’m horrified, I’m sick about what the government of the US is doing to citizens and non-citizens alike.https://www.wordtothewise.com/2026/01/dont-send-customer-generated-content/Mon, 19 Jan 2026 14:03:38 +0000https://www.wordtothewise.com/2026/01/dont-send-customer-generated-content/I just got this email: SPF is valid. It passes DKIM for zoom.us.https://www.wordtothewise.com/2025/12/ipv4-and-ipv6/Tue, 16 Dec 2025 13:32:42 +0000https://www.wordtothewise.com/2025/12/ipv4-and-ipv6/ There are two Internets There are two separate Internets, the Old Internet and the New Internet. They might travel over the same ethernet cables or wifi, but they’re quite separate and rarely directly interact with each other.https://www.wordtothewise.com/2025/12/lets-talk-reengagement/Fri, 05 Dec 2025 10:08:20 +0000https://www.wordtothewise.com/2025/12/lets-talk-reengagement/I appear to have written a lot about about re-engagement on the Email Geeks slack channel the last few days. The problem with slack is it’s not great at archiving or keeping information in an accessible, searchable manner. So, I’ve pulled together the answers, rearranged it, made it slightly more coherent and a little less stream of consciousness, so I can reference this when the topic comes up again.https://www.wordtothewise.com/2025/11/folding-email-headers/Fri, 21 Nov 2025 12:36:29 +0000https://www.wordtothewise.com/2025/11/folding-email-headers/Why are my DKIM signatures failing at Microsoft? There are several reasons why your DKIM signatures might be failing at Microsoft, but perhaps not at other major providers. Many of them are triggered by sending mail that’s “badly structured” in some way. This is one of them.https://www.wordtothewise.com/2025/11/undisclosed-recipients/Fri, 14 Nov 2025 13:17:06 +0000https://www.wordtothewise.com/2025/11/undisclosed-recipients/To: Undisclosed recipients:; Very occasionally you’ll see something in the To: header of an email that isn’t the email addresses you expect, instead it’s the string Undisclosed recipients:;. What does that mean?https://www.wordtothewise.com/2025/10/b2b-spam-strapi-unstructured-and-reo/Fri, 17 Oct 2025 12:32:23 +0100https://www.wordtothewise.com/2025/10/b2b-spam-strapi-unstructured-and-reo/About a year ago I was rebuilding this blog, moving it from WordPress to … something else. I evaluated several content management systems for that, and one of them was Strapi.https://www.wordtothewise.com/2025/09/changes-happen-even-if-you-dont-keep-up/Wed, 24 Sep 2025 12:57:31 +0100https://www.wordtothewise.com/2025/09/changes-happen-even-if-you-dont-keep-up/I cannot count the number of times I hear someone complain that they didn’t change anything and now their email isn’t delivering and why did this happen all of a sudden and how can they be blocked now when they weren’t blocked 3 months ago. Nothing changed, so why all of a sudden is mail failing?https://www.wordtothewise.com/2025/09/laposte-net-will-be-requiring-all-email-to-be-authenticated/Thu, 04 Sep 2025 15:21:41 +0100https://www.wordtothewise.com/2025/09/laposte-net-will-be-requiring-all-email-to-be-authenticated/ Starting on September 9th laposte.net will begin requiring email to have valid, aligned authentication. Mail that isn’t authenticated will start to be delivered to the spam folder or rejected at delivery time.https://www.wordtothewise.com/2025/08/yahoos-mailboxes-are-full/Fri, 29 Aug 2025 17:37:26 +0100https://www.wordtothewise.com/2025/08/yahoos-mailboxes-are-full/ 552 5.2.2 This message could not be delivered because the recipient’s mailbox is full. Please try again later or contact the recipient directly. See https://senders.yahooinc.com/smtp-error-codes#mailbox-full for more informationhttps://www.wordtothewise.com/2025/08/deliverability-rules/Mon, 18 Aug 2025 14:34:42 +0100https://www.wordtothewise.com/2025/08/deliverability-rules/Hot Take: Anyone who has to know exactly what the rules are for inbox delivery is trying to figure out how close they can get to violating the rules without negative consequences. Senders that comply with the spirit of the rules don’t care what the specifics of the rules are.https://www.wordtothewise.com/2025/08/message-id-syntax/Tue, 12 Aug 2025 12:49:47 +0100https://www.wordtothewise.com/2025/08/message-id-syntax/Our friends in the Email Geeks slack have recently started seeing sporadic rejections due to invalid Message-ID headers.https://www.wordtothewise.com/2025/07/dont-make-your-dns-ttls-too-short/Mon, 21 Jul 2025 13:02:17 +0100https://www.wordtothewise.com/2025/07/dont-make-your-dns-ttls-too-short/DNS is a complex, distributed database built on top of an unreliable network that spans the world.https://www.wordtothewise.com/2025/07/gmail-says-your-unsubscribe-needs-work/Fri, 11 Jul 2025 15:05:00 +0100https://www.wordtothewise.com/2025/07/gmail-says-your-unsubscribe-needs-work/ Needs work? We’ve written about RFC 8058 “one-click” unsubscribe and how it’s part of the requirements for bulk senders wanting to deliver mail to the major consumer mailbox providers.https://www.wordtothewise.com/2025/06/about-that-cold-email/Mon, 23 Jun 2025 15:33:20 +0100https://www.wordtothewise.com/2025/06/about-that-cold-email/Over the years I’ve made the decision to stop working with certain types of senders. Most recently it’s been the decision to not work with companies sending cold email. I even wrote a blog post back in 2018 about my frustration with clients who were upset their cold email was going to the spam folder. That was the beginning of the end for cold emailers as clients. I did continue to try and work with those senders, but they were incredibly frustrating engagements. I’d offer all my best practices, even try and work out how they could continue to use their purchased lists. They simply didn’t listen, they just didn’t want to hear that deliverability isn’t just about numbers and they couldn’t metric their way into the inbox. What they really wanted was me to tell them the One Weird Trick that would get their mail into the inbox.https://www.wordtothewise.com/2025/06/you-cant-dkim-sign-a-cabbage/Wed, 18 Jun 2025 09:08:08 +0100https://www.wordtothewise.com/2025/06/you-cant-dkim-sign-a-cabbage/ The DKIM specification and implementations of DKIM signing and validation code make some unstated assumptions about the environment they’re running in.https://www.wordtothewise.com/2025/06/the-challenges-of-b2b-deliverability/Tue, 03 Jun 2025 20:52:32 +0100https://www.wordtothewise.com/2025/06/the-challenges-of-b2b-deliverability/Tomorrow Laura will be giving a webinar as part of the MarketingProfs Summer series. She’ll be speaking specifically about Rising to the Challenge of B2B Deliverability. This talk discusses the fundamental differences between business and consumer mailboxes and how we can’t just apply consumer mailbox deliverability advice to a business environment.https://www.wordtothewise.com/2025/05/swaks-on-macos/Wed, 21 May 2025 12:41:28 +0100https://www.wordtothewise.com/2025/05/swaks-on-macos/SWAKS is my favorite SMTP debugging tool. A new SMTP server I’m building loses pipelining synchronization when connecting via TLS, and I’m sure the bug will be simple to spot if I can send some test messages in to it and watch the sequence of commands. SWAKS is perfect for that.https://www.wordtothewise.com/2025/04/deliverability-summit-amsterdam/Wed, 02 Apr 2025 10:27:09 +0100https://www.wordtothewise.com/2025/04/deliverability-summit-amsterdam/ We’ll be speaking at the Deliverability Summit in Amsterdam on April 24th and 25th.https://www.wordtothewise.com/2025/03/google-and-alignment-update/Fri, 28 Mar 2025 15:30:43 +0000https://www.wordtothewise.com/2025/03/google-and-alignment-update/Earlier this month, I published a post about some changes with how Google is displaying information related to authentication in their “View Original” page. There’s one condition I apparently didn’t report and it brought up a question earlier today.https://www.wordtothewise.com/2025/03/what-spamtraps-tell-us/Fri, 14 Mar 2025 16:42:40 +0000https://www.wordtothewise.com/2025/03/what-spamtraps-tell-us/Many blocklists use spamtraps to detect poor sending practices and will cite spamtrap hits as the reason for the blocks. Senders legitimately fear spamtraps showing up on their lists because of this. If spamtraps weren’t used by blocklists no one would really care about them. They’re just another kind of bad address.https://www.wordtothewise.com/2025/03/do-spamtraps-exist/Thu, 13 Mar 2025 11:52:36 +0000https://www.wordtothewise.com/2025/03/do-spamtraps-exist/One of the folks on the Email Geeks slack asked me a question last week that I thought was really insightful and has a somewhat nuanced answer.https://www.wordtothewise.com/2025/03/google-alignment-and-dmarc/Tue, 11 Mar 2025 12:02:35 +0000https://www.wordtothewise.com/2025/03/google-alignment-and-dmarc/Google has been making a number of changes to their systems over the last few weeks. Folks are seeing a lot of changes in Google postmaster tools and they’re seeing changes in how Google is displaying headers in the “show original” tab.https://www.wordtothewise.com/2025/02/setting-up-a-smarthost/Fri, 28 Feb 2025 15:43:36 +0000https://www.wordtothewise.com/2025/02/setting-up-a-smarthost/We run most of our own network services – inbound and outbound email, DNS and web presence. We run separate services for inbound and outbound email to give us more flexibility in how we set things up.https://www.wordtothewise.com/2025/02/how-to-choose-an-esp-based-on-deliverability/Mon, 10 Feb 2025 11:22:33 +0000https://www.wordtothewise.com/2025/02/how-to-choose-an-esp-based-on-deliverability/Despite what a lot of SEO slop will try and tell you there’s no way to measure deliverability performance across multiple ESPs in any way that’s meaningful.https://www.wordtothewise.com/2025/02/dont-add-your-domain-to-the-public-suffix-list/Wed, 05 Feb 2025 16:14:14 +0000https://www.wordtothewise.com/2025/02/dont-add-your-domain-to-the-public-suffix-list/(At least, not if you ever intend to use it for email. It might break the domain for email, maybe forever.)https://www.wordtothewise.com/2025/01/are-complaints-weighted/Fri, 31 Jan 2025 11:47:37 +0000https://www.wordtothewise.com/2025/01/are-complaints-weighted/I’ve been doing a lot of my question answering over on the Email Geeks slack and have decided to bring some of the answers over here. Today’s question:https://www.wordtothewise.com/2025/01/diagnosing-hard-bounces/Tue, 28 Jan 2025 10:43:46 +0000https://www.wordtothewise.com/2025/01/diagnosing-hard-bounces/A very short post about diagnosing hard bounces, because I’ve had to give the same advice to a dozen folks over the past few months.https://www.wordtothewise.com/2025/01/effects-of-the-yahoo-and-google-changes/Thu, 23 Jan 2025 11:31:00 +0000https://www.wordtothewise.com/2025/01/effects-of-the-yahoo-and-google-changes/In October 2023, Yahoo and Google announced new standards for sending bulk mail to their systems. For bulk senders these changes included requiring aligned authentication and publishing a DMARC record and complying with the List-Unsubscribe RFC. The ISPs also formally announced complaints must stay below a threshold of 0.3%. At the time of the announcement, they said enforcement would start in February 2024. As with many things, this enforcement deadline was pushed as ESPs explained the challenges to meet the deadlines.https://www.wordtothewise.com/2024/12/stop-using-entrust-for-your-bimi-certificates/Tue, 31 Dec 2024 15:57:56 +0000https://www.wordtothewise.com/2024/12/stop-using-entrust-for-your-bimi-certificates/In July I talked about how Entrust was mistrusted by, well, pretty much everyone due to a years long series of security and trust violations.https://www.wordtothewise.com/2024/12/tracking-link-maths/Tue, 10 Dec 2024 13:35:31 +0000https://www.wordtothewise.com/2024/12/tracking-link-maths/ How long does a tracking link need to be?https://www.wordtothewise.com/2024/11/theres-text-and-then-theres-text/Thu, 28 Nov 2024 16:00:37 +0000https://www.wordtothewise.com/2024/11/theres-text-and-then-theres-text/If you want to send someone an email with some text in it there are quite a few different ways you can do it. The main differences are the ways the text is packaged up in MIME entities to be sent.https://www.wordtothewise.com/2024/11/your-bounce-classification-is-a-bit-rubbish/Tue, 26 Nov 2024 09:14:18 +0000https://www.wordtothewise.com/2024/11/your-bounce-classification-is-a-bit-rubbish/When a mailbox provider rejects or defers an email it sends back a message explaining why.https://www.wordtothewise.com/2024/11/do-we-care-about-spf-alignment/Fri, 22 Nov 2024 08:27:40 +0000https://www.wordtothewise.com/2024/11/do-we-care-about-spf-alignment/SPF and DKIM are the two main ways we associate a domain name with a stream of email in an authenticated way. We can choose the DKIM signing domain fairly freely – we can choose any domain or subdomain we control and put it in the d= field of the DKIM signature. But our choice for the SPF domain is more constrained.https://www.wordtothewise.com/2024/11/comparing-dkim-keys/Wed, 20 Nov 2024 13:53:47 +0000https://www.wordtothewise.com/2024/11/comparing-dkim-keys/Sometimes we have a client who has done something wrong when setting up authentication. Their DKIM signing fails due to something being wrong with the public key they’ve published.https://www.wordtothewise.com/2024/10/the-future-of-deliverability/Wed, 30 Oct 2024 18:19:29 +0000https://www.wordtothewise.com/2024/10/the-future-of-deliverability/There always seems to be appetite from folks to read the tea leaves and follow up with predictions about what the future holds. I mean, how many folks in the US are obsessively refreshing polls for the last few weeks? (American’s: don’t forget to vote on Tuesday!)https://www.wordtothewise.com/2024/08/no-gmail-did-not-just-break-all-open-tracking/Thu, 29 Aug 2024 11:54:53 +0100https://www.wordtothewise.com/2024/08/no-gmail-did-not-just-break-all-open-tracking/I was avoiding commenting on the email open tracking bad take that seems to be going viral round the more gullible corners of LinkedIn.https://www.wordtothewise.com/2024/08/dns-failures/Wed, 28 Aug 2024 12:13:35 +0100https://www.wordtothewise.com/2024/08/dns-failures/We use DNS a lot in email, particularly for authentication, so diagnosing why DNS isn’t returning what we expect it to is a pretty common challenge. And DNS responses aren’t exactly the clearest thing to understand.https://www.wordtothewise.com/2024/08/the-economics-of-cold-outreach/Mon, 12 Aug 2024 10:08:36 +0100https://www.wordtothewise.com/2024/08/the-economics-of-cold-outreach/It’s time we talk about cold outreach mail. In the last 2 years the volume and aggressiveness of cold outreach mail seems to have exploded. There are dozens of companies out there who are selling services to companies to facilitate cold outreach. My own sales mailbox is full of requests from companies to help them solve their delivery problems.https://www.wordtothewise.com/2024/08/bears-and-spam-filters/Fri, 09 Aug 2024 13:10:21 +0100https://www.wordtothewise.com/2024/08/bears-and-spam-filters/“Why is my inbox full of spam, while I still can’t get the mail I send into the inbox reliably?” — most email marketers at some point in their career.https://www.wordtothewise.com/2024/08/prefetches-and-proxies/Tue, 06 Aug 2024 14:41:29 +0100https://www.wordtothewise.com/2024/08/prefetches-and-proxies/Jody asks “Are ‘prefetch opens’ and ‘proxy opens’ the same thing?”https://www.wordtothewise.com/2024/07/sendy-and-one-click-unsubscribe/Sat, 13 Jul 2024 10:29:37 +0100https://www.wordtothewise.com/2024/07/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.https://www.wordtothewise.com/2024/07/sending-domains-and-hostnames/Fri, 12 Jul 2024 14:20:06 +0100https://www.wordtothewise.com/2024/07/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.https://www.wordtothewise.com/2024/07/if-youre-using-entrust-for-your-bimi-vmc/Tue, 02 Jul 2024 09:10:10 +0100https://www.wordtothewise.com/2024/07/if-youre-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.https://www.wordtothewise.com/2024/06/dmarc-the-good-the-bad-and-the-ugly/Fri, 21 Jun 2024 09:50:38 +0100https://www.wordtothewise.com/2024/06/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.https://www.wordtothewise.com/2024/06/whos-your-email-czar/Fri, 21 Jun 2024 07:55:13 +0100https://www.wordtothewise.com/2024/06/whos-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, Udoria, Obdoria, Kondia and Master of all the Siberian Lands and Northern Countries.https://www.wordtothewise.com/2024/06/why-deliverability-depends/Thu, 20 Jun 2024 12:45:49 +0100https://www.wordtothewise.com/2024/06/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.https://www.wordtothewise.com/2024/06/deliveries-and-opens-and-clicks/Thu, 20 Jun 2024 10:18:12 +0100https://www.wordtothewise.com/2024/06/deliveries-and-opens-and-clicks/ I always want to say “Emails, and Opens, and Clicks… Oh My!” when I’m talking about them.https://www.wordtothewise.com/2024/06/warmup-is-communication/Wed, 19 Jun 2024 09:41:33 +0100https://www.wordtothewise.com/2024/06/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 antennas—he’s the controller—and they wait for the airplanes to land. They’re doing everything right. The form is perfect. It looks exactly the way it looked before. But it doesn’t work. No airplanes land. — Richard Feynmanhttps://www.wordtothewise.com/2024/06/filter-evasion/Wed, 19 Jun 2024 09:18:19 +0100https://www.wordtothewise.com/2024/06/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.https://www.wordtothewise.com/2024/06/why-deliverability-matters/Tue, 18 Jun 2024 13:10:00 +0100https://www.wordtothewise.com/2024/06/why-deliverability-matters/ Deliverability matters because we are the conscience of our companies. We are the ones who tell our companies, and particularly the marketing team, no. We’re the ones looking out for the health of our company reputation, the recipient’s inbox and the email ecosystem as a whole.https://www.wordtothewise.com/2024/06/deliverability-is-collaborative/Tue, 18 Jun 2024 08:39:46 +0100https://www.wordtothewise.com/2024/06/deliverability-is-collaborative/ Mailbox providers want happy recipients Mailbox providers want their users to be happy with the mail they receive and the service they get. That’s driven by stark business reasons: acquiring new users is costly, happy users bring in revenue – whether directly, or indirectly via advertising – and their word of mouth helps bring in more users, and hence more revenue. That’s still true when the email service is bundled as part of a larger package, such as broadband service or domain registration.https://www.wordtothewise.com/2024/06/why-deliverability-matters-to-me/Mon, 17 Jun 2024 11:39:58 +0100https://www.wordtothewise.com/2024/06/why-deliverability-matters-to-me/ Welcome to deliverability week. I want to especially thank Al for doing a lot of work behind the scenes herding this group of cats. He’s an invaluable asset to the community.https://www.wordtothewise.com/2024/06/deliverability-week-2024/Mon, 17 Jun 2024 11:37:22 +0100https://www.wordtothewise.com/2024/06/deliverability-week-2024/ What is Deliverability Week? Al Iverson decided it should happen, and asked a bunch of deliverability folks to share some of their thoughts about the deliverability industry – why do we do this? where did we come from? what’s next?https://www.wordtothewise.com/2024/06/deliverability-week/Mon, 10 Jun 2024 09:07:35 +0100https://www.wordtothewise.com/2024/06/deliverability-week/ Next week everyone will be talking Deliverability.https://www.wordtothewise.com/2024/06/swaks-test-your-smtp/Wed, 05 Jun 2024 13:18:32 +0100https://www.wordtothewise.com/2024/06/swaks-test-your-smtp/We’ve mentioned SWAKS here a few times – but I always use it for delivering test mail directly to a recipient’s MX.https://www.wordtothewise.com/2024/04/no-google-doesnt-hate-reactive-design/Fri, 19 Apr 2024 11:48:02 +0100https://www.wordtothewise.com/2024/04/no-google-doesnt-hate-reactive-design/I’ve seen a bunch of folks panic about some phrasing in Google’s Email sender guidelines.https://www.wordtothewise.com/2024/04/dns-for-white-label-authentication-with-sproutdns/Thu, 18 Apr 2024 15:07:08 +0100https://www.wordtothewise.com/2024/04/dns-for-white-label-authentication-with-sproutdns/I wrote last year about using “stunt” nameservers for customer subdomain authentication – i.e. dynamically generating all the authentication records needed in DNS for each customer as needed.https://www.wordtothewise.com/2024/04/deliverability-summit-2024/Thu, 18 Apr 2024 13:31:51 +0100https://www.wordtothewise.com/2024/04/deliverability-summit-2024/We just got back from Amsterdam a couple of days ago, after attending the Deliverability Summit.https://www.wordtothewise.com/2024/03/anatomy-of-a-received-header/Wed, 27 Mar 2024 17:18:08 +0000https://www.wordtothewise.com/2024/03/anatomy-of-a-received-header/When trying to find out why Something Went Wrong during delivery of an email we sometimes want to look at the route by which it was delivered.https://www.wordtothewise.com/2024/03/looking-back-looking-forward/Sat, 23 Mar 2024 13:51:03 +0000https://www.wordtothewise.com/2024/03/looking-back-looking-forward/Six years ago today I wrote here “Spam isn’t going away“, talking about systemic problems at Google, Cloudflare and Amazon and in India.https://www.wordtothewise.com/2024/02/errors-in-dkim-records/Wed, 28 Feb 2024 14:37:35 +0000https://www.wordtothewise.com/2024/02/errors-in-dkim-records/TXT Records DKIM public keys live in DNS TXT records. A DNS TXT record contains strings of text, and each string is limited to be no more than 255 characters long.https://www.wordtothewise.com/2024/01/one-click-unsubscribe/Wed, 31 Jan 2024 13:23:43 +0000https://www.wordtothewise.com/2024/01/one-click-unsubscribe/The worst thing about the yahoogle requirements has been their use of the term “one-click unsubscribe”. It’s an overloaded term that’s being used here to mean RFC 8058 in-app unsubscription. That’s a completely different thing to what one-click unsubscription has been used to mean for decades, often in the context of complying with legal requirements around unsubscription.https://www.wordtothewise.com/2024/01/dont-trust-gmails-show-original/Wed, 17 Jan 2024 17:14:15 +0000https://www.wordtothewise.com/2024/01/dont-trust-gmails-show-original/It’s not always easy to know what the actual headers and body of an email as sent look like. For a long time accepted wisdom was that you could send a copy to your gmail account, and use the Show Original menu option to, well, see the original message as raw text.https://www.wordtothewise.com/2024/01/are-you-a-grown-up-sender/Fri, 05 Jan 2024 14:30:26 +0000https://www.wordtothewise.com/2024/01/are-you-a-grown-up-sender/Yes, it’s another yahoogle best practices post. Google divide their requirements for senders into those sending more than 5,000 messages a day, and those sending less.https://www.wordtothewise.com/2024/01/yahoogle-faqs/Thu, 04 Jan 2024 15:16:00 +0000https://www.wordtothewise.com/2024/01/yahoogle-faqs/Just a very, very short post with links to the Yahoo and Google requirements FAQs. Given I can’t ever remember them I’m guessing lots of y’all can’t either.https://www.wordtothewise.com/2024/01/answers-to-your-questions-about-the-new-yahoo-and-google-technical-requirements/Wed, 03 Jan 2024 14:09:42 +0000https://www.wordtothewise.com/2024/01/answers-to-your-questions-about-the-new-yahoo-and-google-technical-requirements/On January 9th at 6pm GMT, 1pm EST and 10am PST I’ll be speaking with Nout Boctor-Smith of Nine Lives Digital about the new Yahoo and Google technical requirements.https://www.wordtothewise.com/2024/01/about-my-email/Tue, 02 Jan 2024 14:01:17 +0000https://www.wordtothewise.com/2024/01/about-my-email/Happy 2024, everyone! We’ve released a shiny new tool to let folks self-check a lot of common questions we see about email requirements.https://www.wordtothewise.com/2023/11/tis-the-season-2/Tue, 21 Nov 2023 11:54:40 +0000https://www.wordtothewise.com/2023/11/tis-the-season-2/https://www.wordtothewise.com/2023/11/yahoogle-requirements-update/Thu, 09 Nov 2023 14:01:20 +0000https://www.wordtothewise.com/2023/11/yahoogle-requirements-update/Since I wrote about it last month the requirements for bulk senders to Yahoo and Google have changed a little.https://www.wordtothewise.com/2023/10/can-you-starttls/Wed, 25 Oct 2023 09:40:51 +0100https://www.wordtothewise.com/2023/10/can-you-starttls/Email supports TLS (Transport Layer Security), what we used to call SSL.https://www.wordtothewise.com/2023/10/customer-subdomain-authentication/Fri, 20 Oct 2023 14:50:09 +0100https://www.wordtothewise.com/2023/10/customer-subdomain-authentication/EDIT: Now with a production-ready implementation I talk about more here.https://www.wordtothewise.com/2023/10/wildcards-and-dkim-and-dmarc-oh-my/Wed, 18 Oct 2023 11:34:08 +0100https://www.wordtothewise.com/2023/10/wildcards-and-dkim-and-dmarc-oh-my/If you’re an ESP with small customers you may have looked at the recent Google / Yahoo requirements around DMARC-style alignment for authentication and panicked a bit.https://www.wordtothewise.com/2023/10/deferrals-at-microsoft/Wed, 11 Oct 2023 11:28:22 +0100https://www.wordtothewise.com/2023/10/deferrals-at-microsoft/If you’re seeing a lot of “451 4.7.500 Server busy. Please try again later” from Office365 this morning you’re not alone.https://www.wordtothewise.com/2023/10/when-asking-a-question/Thu, 05 Oct 2023 11:30:32 +0100https://www.wordtothewise.com/2023/10/when-asking-a-question/A lot of beginner questions about email delivery aren’t about broad strategies for success, or technical details about authentication, or concerns about address acquisition. They’re something like:https://www.wordtothewise.com/2023/10/new-requirements-for-bulk-senders/Tue, 03 Oct 2023 16:18:19 +0100https://www.wordtothewise.com/2023/10/new-requirements-for-bulk-senders/UPDATE: You need to authenticate with both DKIM and SPF.https://www.wordtothewise.com/2023/09/validity-charging-for-feedback-loop-emails/Thu, 14 Sep 2023 08:16:37 +0100https://www.wordtothewise.com/2023/09/validity-charging-for-feedback-loop-emails/History Return Path was a major driver for the establishment of Feedback Loops (FBLs) back in the mid to late 2000s. They worked with a number of ISPs to help them set up FBLs and managed the signup and validation step for them. In return for providing this service to senders and receivers, they used this data as part of their certification process and their deliverability consulting. Return Path had a strong corporate ethos of improving the overall email ecosystem that originated from the CEO and permeated through the whole organization.https://www.wordtothewise.com/2023/09/the-trouble-with-cnames/Thu, 07 Sep 2023 15:06:49 +0100https://www.wordtothewise.com/2023/09/the-trouble-with-cnames/When you query DNS for something you ask your local DNS recursive resolver for all answers it has about a hostname of a certain type. If you’re going to a website your browser asks your resolver for all records for “google.com” of type “A”1or “AAAA”, but that’s not important right now and it will either return all the A records for google.com it has cached, or it will do the complex process of looking up the results from the authoritative servers, cache them for as long as the TTL field for the reply says it should, then return them to you.https://www.wordtothewise.com/2023/08/unsubscribe-vs-suppress/Fri, 04 Aug 2023 13:17:16 +0100https://www.wordtothewise.com/2023/08/unsubscribe-vs-suppress/When someone sends a complaint to your compliance desk there are a range of things you want to do, but one thing you always want to do is ensure that the recipient doesn’t receive any more unwanted email from your customer. Or, at least, not from your network.https://www.wordtothewise.com/2023/07/how-to-unsubscribe/Wed, 26 Jul 2023 10:56:22 +0100https://www.wordtothewise.com/2023/07/how-to-unsubscribe/Eventually our subscribers won’t want our email in their inbox any more.https://www.wordtothewise.com/2023/07/the-case-of-the-500-mile-email/Fri, 21 Jul 2023 09:41:47 +0100https://www.wordtothewise.com/2023/07/the-case-of-the-500-mile-email/I stumbled across this story again this morning, and it’s such a lovely delivery yarn I thought I’d share it.https://www.wordtothewise.com/2023/06/ios17-filtering-click-tracking-links/Tue, 27 Jun 2023 14:57:06 +0100https://www.wordtothewise.com/2023/06/ios17-filtering-click-tracking-links/I’ve heard quite a bit of concern about what iOS 17’s automatic removal of click-tracking parameters means, but less discussion of what it actually does.https://www.wordtothewise.com/2023/06/they-must-have-changed-something/Tue, 13 Jun 2023 17:23:50 +0100https://www.wordtothewise.com/2023/06/they-must-have-changed-something/One of the most common refrains I hear from folks with delivery problems is that the filters must have changed because their mail suddenly started to go to the bulk folder. A few years ago, I posted about how even when there is no change in the sender’s behavior, reputation can slowly erode until mail suddenly goes to the Gmail bulk folder. Much of that still applies – although the comments on pixel loads (what other folks call ‘open rates’) are a bit outdated due to changes in Gmail behavior.https://www.wordtothewise.com/2023/06/is-this-email-address-disposable/Thu, 08 Jun 2023 12:40:00 +0100https://www.wordtothewise.com/2023/06/is-this-email-address-disposable/As a consumer there are several different sorts of email address that are described as “disposable” or “temporary”.https://www.wordtothewise.com/2023/06/c-is-for-cookie/Thu, 01 Jun 2023 18:03:03 +0100https://www.wordtothewise.com/2023/06/c-is-for-cookie/Trekkie Monster. He’s obsessed by social media and isn’t owned by Children’s Television Workshop. What is a Cookie? I’m not talking about biscuits, nor about web cookies, at least not exactly.https://www.wordtothewise.com/2023/05/unresolvable-rfc-5321-domain-at-yahoo/Tue, 30 May 2023 15:55:48 +0100https://www.wordtothewise.com/2023/05/unresolvable-rfc-5321-domain-at-yahoo/Seen this recently? 451 Message temporarily deferred due to unresolvable RFC.5321 from domain; see https://postmaster.yahooinc.com/error-codeshttps://www.wordtothewise.com/2023/05/is-edu-a-canary/Fri, 26 May 2023 11:45:30 +0100https://www.wordtothewise.com/2023/05/is-edu-a-canary/Several times recently I’ve heard about something unusual happening email delivery-wise at academic domains that was new, and wasn’t being seen at non-academic domains on the same lists.https://www.wordtothewise.com/2023/05/want-a-link-on-wttw/Tue, 09 May 2023 17:48:19 +0100https://www.wordtothewise.com/2023/05/want-a-link-on-wttw/There is an ever increasing amount of spam I am getting from various companies asking for links here on WttW.https://www.wordtothewise.com/2023/05/is-email-dead/Fri, 05 May 2023 15:47:47 +0100https://www.wordtothewise.com/2023/05/is-email-dead/These last few years have been something, huh? Something had to give and, in my case, that something was blogging. There were a number of reasons I stopped writing here, many of them personal, some of them more global. I will admit, I was (and still am a little) burned out as it seemed I was saying and writing the same things I’d been saying and writing for more than a decade. Taking time off has helped a little bit, as much to focus on what I really want to talk about.https://www.wordtothewise.com/2023/05/friendly-from-addresses/Mon, 01 May 2023 14:02:20 +0100https://www.wordtothewise.com/2023/05/friendly-from-addresses/When we’re looking at the technical details of email addresses there are two quite different contexts we talk about.https://www.wordtothewise.com/2023/04/dont-break-the-rfc-rules/Fri, 28 Apr 2023 09:39:08 +0100https://www.wordtothewise.com/2023/04/dont-break-the-rfc-rules/It looks like Microsoft are getting pickier about email address syntax, rejecting mail that uses illegal address formats. That might be what’s causing that “550 5.6.0 CAT.InvalidContent.Exception: DataSourceOperationException, proxyAddress: prefix not supported – ; cannot handle content of message” rejection.https://www.wordtothewise.com/2022/10/life-of-an-email/Wed, 19 Oct 2022 09:53:50 +0100https://www.wordtothewise.com/2022/10/life-of-an-email/I’m repeating the presentation I gave at M3AAWG in London for the Certified Senders Alliance.It’s all about how to send an email by hand, and how knowing the mechanics of how an email is sent can help us diagnose email delivery issues.We’re starting in about five hours from when I post this.Register at https://register.gotowebinar.com/register/2268789893122531343https://www.wordtothewise.com/2022/09/gmail-program-for-election-mail/Thu, 15 Sep 2022 16:24:49 +0100https://www.wordtothewise.com/2022/09/gmail-program-for-election-mail/A few months ago, Google made a splash in the political press and the email marketing space when they asked the FEC the following question:https://www.wordtothewise.com/2022/07/confidential-to-esps/Thu, 28 Jul 2022 10:42:21 +0100https://www.wordtothewise.com/2022/07/confidential-to-esps/Dear Colleagues at ESPs, We have a problem. More specifically, YOU have a problem. You have a spam problem. One that you’re not taking care of in any way, shape or form.https://www.wordtothewise.com/2022/07/when-best-practices-dont-work/Wed, 06 Jul 2022 12:40:22 +0100https://www.wordtothewise.com/2022/07/when-best-practices-dont-work/I started out with the best intentions to get back into the swing of things with blogging more regularly. But between MAAWG recovery, COVID recovery and life it’s not worked out that way.https://www.wordtothewise.com/2022/06/sending-email/Tue, 14 Jun 2022 16:53:22 +0100https://www.wordtothewise.com/2022/06/sending-email/I did a class at M3AAWG teaching the basic mechanics of sending an email, both really by hand using dig and netcat, and using SWAKS. No slides, but if you’re interested in the script I’ve posted a very rough copy of my working notes here.https://www.wordtothewise.com/2022/06/the-gang-is-trickling-in/Mon, 13 Jun 2022 11:29:50 +0100https://www.wordtothewise.com/2022/06/the-gang-is-trickling-in/It’s been a few years since we’ve actually made it to a MAAWG. We missed much of 2018 and 2019 due to our international move. Then 2020 San Francisco conflicted with a personal engagement. Then, well, pandemic hit and it’s been virtual and then we were moving and … wow, it’s been busy!https://www.wordtothewise.com/2022/06/esps-need-to-step-up-their-compliance-game/Mon, 06 Jun 2022 09:51:16 +0100https://www.wordtothewise.com/2022/06/esps-need-to-step-up-their-compliance-game/I don’t send a lot of spam complaints generally. Mostly I block and move on. There are some companies, though, that I offer the professional courtesy of sending a complaint or a report to their abuse@ address. Former clients, friends and colleagues generally get that courtesy.