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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SMTP rejections are up: One reason why might surprise you!

SMTP rejections are up: One reason why might surprise you!

Ouch, what a click-baitey headline. But let’s run with it, because it comes from an honest place. As I mentioned here and elsewhere, I recently teamed up with Scott Ziegler from Valimail for a webinar digging into SMTP rejection data provided by Google starting in July/August 2025, and what we saw from this data going into Black Friday and Cyber Monday. There was quite a large number of SMTP rejections in the data. Some of it for the usual reasons: spam/reputation, failing SPF or DKIM, etc. etc. …

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The Latest Deliverability News

SMTP rejections are up: One reason why might surprise you!

Ouch, what a click-baitey headline. But let’s run with it, because it comes from an honest place. As I mentioned here and elsewhere, I recently teamed up with Scott Ziegler from Valimail for a webinar digging into SMTP rejection data provided by Google starting in July/August …

From and reply to: Routability and matching domains?

Here’s a question that comes up enough that I’ve got multiple versions of it sitting in my blog scratchpad, just waiting for me to draft my thoughts. And I've got thoughts! Let me share those thoughts, just after sharing the the two main versions of this question that I'…

RNC v. Google Ninth Circuit appeal fails

Eric Goldman, writing for his Technology & Marketing Law Blog, has just shared an update in the RNC v. Google saga , this time the Ninth Circuit wastes very little time shutting the whole thing down. If you remember the earlier round, the Republican National Committee claim…

Spam Resource Spotlight: Chad S. White

Chad S. White is Group Vice President of CRM Strategy for Zeta Global. He is also the publisher of EmailMarketingRules.com , a blog and resource hub that serves as a definitive guide for marketers looking to master the complexities of email. Grounded in the frameworks of his cr…

When DMARC breaks: Failures fixed & other stories of support success

Webinar alert! Join me, Al Iverson, community and industry person her at DMARC provider Valimail for a chat on January 22nd talking through common ways DMARC implementations go wrong, why “doing it yourself” gets so tricky, and how hands-on, expert support can mean the differe…

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…