Spam Resource: All Things Deliverability
I'm Al Iverson and I'm here to help. You've got questions about email deliverability? Find answers here! This is where I've been writing about email technology, sender requirements and best practices, email authentication, stopping spam, and more, for twenty-four years. And if you can't find an answer in one of the 1700+ articles here, drop me a line with your question, and I'll try my best to follow up. And don't forget to subscribe to my email newsletter, so that you'll get updated info pushed to your inbox weekly.
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Ask Al: January review and reset for email senders

Ask Al: January review and reset for email senders

You survived Black Friday. You survived Cyber Monday. You survived Q4 and 2025. Now what? In my first Ask Al video of 2026 , I walk through what January should look like for email senders once the dust settles. This is the window where you can safely review, fix, and plan without risking revenue or inbox placement. I cover what to look at now that Q4 is behind you, including: Planning 2026 sending volume and infrastructure now, while you have the time Reviewing DNS for existing sending IPs and domain…

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Ask Al: January review and reset for email senders

You survived Black Friday. You survived Cyber Monday. You survived Q4 and 2025. Now what? In my first Ask Al video of 2026 , I walk through what January should look like for email senders once the dust settles. This is the window where you can safely review, fix, and plan witho…

Dead domain: worldnet.att.net

AT&T as an internet provider and mailbox provider has been around for a while, surviving through various iterations over the years. Once upon a time (starting in 1996) that was dialup internet branded as " AT&T Worldnet ," with customers being provided email a…

Gmail announces A.I. inbox: What does this mean?

In my recent “ 2026 predictions ” blog post, one of the things I touched on was Artificial Intelligence. I mentioned that while it was certainly a component of deliverability, it is mostly already driving spam filters in ways you’re already accounting for, so don’t really worry…

Ask Al: 18 Months, 61 Videos

Just around eighteen months ago, I started work on a new video series for my employer, DMARC provider Valimail . The goal? Answer an email related question, usually with a focus of email deliverability or email authentication, with a short video, every week or two. Thus, “Your …

Zeta: Q3 2025 Email Benchmarks

Looking for benchmark email marketing stats? Zeta Global’s got the data, and they’re not afraid to share . Benchmark data can be a bit of a mixed bag. It can be handy to use as a starting point to know if you’re doing anywhere near okay from a deliverability perspective, but br…

Wait, what is Microsoft SNDS? (for 2026)

Every time I post about changes to Microsoft SNDS, somebody always asks, “What, what is Microsoft SNDS? How do I use it?” And so, to be proactive this time around, allow me to link to this wonderful introductory overview and explainer from fellow deliverability expert, Iterable…

January 2026 Microsoft SNDS Updates (So far)

If you use Microsoft’s SNDS (Smart Network Data Services) online reputation portal to monitor for deliverability and reputation indicators for mail you’re sending to Microsoft OLC (Outlook Consumer, aka Hotmail/Outlook.com) mailboxes, you might have noticed this already. Clear…

Email Deliverability in 2026: What's next?

You’re wondering what deliverability changes await us in 2026? I’m so glad you asked! Let’s talk about deliverability in 2026: What’s here now, how things work today, how it’s all evolving, and what I think things will look like over the coming year. In 2026, Technical Complian…

Survey says: What was your biggest BFCM inbox challenge?

Time to look back on the 2025 holiday marketing season. Black Friday/Cyber Monday (BFCM) is always a challenging time for email senders AND receivers. Email marketers are digging deeper into their email database than other times of year, and often are increasing their send cade…

Coming in the future: Change your Gmail address?

If Ben Schoon, writing for 9to5Google , is to be believed, it sounds like an option could be coming in the future that allows Gmail users to change their email address. I’m really thinking of it almost as an alias address creator or manager, based on the initial description of …

Where does a BIMI logo show?

Here's a question that I was asked recently: Where, exactly, does a BIMI email sender logo show in the inbox (or next to the inbox) in all the different email clients and webmail platforms that support it? I thought it would be fun to demonstrate this visually, so I dug out…

Spam Filters, Black Boxes, and the Illusion of Control

On the surface, email is magic. It just works. Messages go out, inboxes fill up, marketing and newsletters hum along. Underneath that smooth glide is a lot of frantic paddling, and Nick Gallagher's new article for IBM Think does an excellent job showing what is really happ…

Tom Mairs: Combating RCS spam

Tom Mairs is co-founder of Kumo Corp . If you're not familiar, they're " Building the first Open-Source MTA made especially for large-volume senders. " Tom's also got a personal blog full of random musings and I thought it would be useful to link to his v…

Help! I'm seeing 550-5.7.25 errors at Gmail!

Are you seeing this error message when trying to send emails to Gmail? 550-5.7.25 The IP address sending this message does not have a PTR record setup, or the corresponding forward DNS entry does not match the sending IP. As a policy, Gmail does not accept messages from IPs wit…

Top 5 Spam Resource Posts of 2025

As this year rolls its way toward the exit, it is time for my annual roundup of the most popular blog posts published in the year 2025. A lot happened this year, in the world of deliverability. Yahoo Mail is growing, having fully integrated AT&T mailboxes into their backend…