Word to the Wise

We make email better.


We make email better.

Word to the Wise helps email marketers create more effective email messages, programs and infrastructures. We advise you how to skillfully navigate the constant business, technology, and policy challenges so your messages reach your customers.

We can help you with your email strategy, deliverability challenges and many other email issues.

Latest stories

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...

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...

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. There are usually several different ways you can make sure that happens. There are big hammers a compliance desk can use in...

How to Unsubscribe


Eventually our subscribers won’t want our email in their inbox any more. They can stop the mail either by unsubscribing from it, or by marking it as spam. We’d far rather they do the first so we should make it as easy as possible for them to unsubscribe. Also in most jurisdictions you’re legally required to offer a functional, easy to use unsubscription channel. So, how to do...

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. It’s from Trey Harris, and it’s set in the mid 90s. Here's a problem that *sounded* impossible... I almost regret posting the story to a wide audience, because it makes a great tale over drinks at a conference. :-) The story is slightly altered in order to protect...

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. Broadly it’s Apple trying to improve user-privacy by making it harder to do cross-site tracking at scale. Cross-site tracking is the basis of a lot of privacy-violating tracking technologies, and tracking parameters added to...

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...

Is this email address disposable?


As a consumer there are several different sorts of email address that are described as “disposable” or “temporary”. Some of them are what we might call tagged addresses – addresses that are unique, created to be given to a specific vendor. If it’s misused by the vendor, or if it’s leaked to spammers, then the address can be disabled, either by rejecting...

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. When you’re talking to a protocol developer a cookie is a thing you’re given, that you hang on to for a while, then give back. If you leave your suitcase with your hotel...

Unresolvable RFC.5321 domain at Yahoo


Seen this recently? 451 Message temporarily deferred due to unresolvable RFC.5321 from domain; see This is Yahoo doing some extra work to identify that the 5321.From domain1The return-path, aka the 821.From, 5321.From, or bounce address is the email address you send from at the protocol level, not the email address in the From: header, and it’s the address any bounces will be sent to. of...

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