Email Authentication
29 articles
2026 Email Deliverability Review: 9 Changes to Fix Before 2027 Recap of the Unspam.email webinar with Email Industries: Postmaster Tools v2, DMARCbis, DKIM2, Heatwave, Gmail's AI Inbox and Comcast's move to Yahoo. Email Deliverability News 2026: What Changed and When Email deliverability news, newest first and updated monthly: Exchange Online's new sending limits, Gmail's verified senders, Apple's relay domain and RFC 9989. Email Feedback Loops: Only Two of the Big Four Send You One Yahoo and Microsoft send an ARF report naming the recipient who complained. Gmail sends an aggregate rate with no addresses, and Apple offers none. DANE for Email: Who Publishes a TLSA Record and Who Does Not DANE puts your MX certificate fingerprint in DNSSEC-signed DNS. We checked 13 domains on 22 September 2026: the four large providers publish none. ARC: a Finished Experiment You Were Never Meant to Deploy ARC is added by forwarders, not senders, and the IETF asked in April 2026 to mark it Historic. What the chain is, who Apple's ask applies to, and what to read. Return-Path: The Address SPF Checks and Your Reader Never Sees What the Return-Path header is, why SPF authenticates it rather than the From address, how a custom return path earns DMARC alignment, and how to read it. DKIM Key Length: 2048 Bits Does Not Fit in One DNS String Why upgrading a DKIM key to 2048 bits breaks the record, how a truncated key still reports its intended size, and the six checks that catch it. SPF include: Over 10 Lookups Does Not Fail Every Message The SPF include mechanism and the ten DNS lookup limit: which terms cost a lookup, why the count is higher than it looks, and who actually fails. Email Authentication Explained: SPF, DKIM, DMARC and BIMI Email authentication is three DNS records. What SPF, DKIM and DMARC each prove, why alignment is where they fail, and what mailbox providers now require. Best DMARC Monitoring Tools, Measured From 166 Live Records Which DMARC monitoring tools 166 major domains actually use, the five things vendors call free, and why a third reporting address may receive nothing. RFC 9989: DMARC Deleted Three Tags and 46% Still Publish One RFC 9989 removed pct, ri and rf from DMARC in May 2026. What each deletion changes, which one made live records stricter, and how to read yours. Email Subdomain vs Root Domain: What to Send From Should you send marketing email from a subdomain or your root domain? What a sending subdomain really isolates, what crosses anyway, and when not to migrate. DKIM2 and DMARCbis: What Changes Next in Email Authentication DKIM2 signs a message at every hop so forwarding no longer breaks authentication. Where the IETF draft stands, what DMARCbis changes, and what to do now. Email Authentication Checklist: SPF, DKIM, DMARC, ARC, BIMI A per-protocol checklist for SPF, DKIM, DMARC, ARC and BIMI: what each standard does and the settings to get right for each one before you send. Reverse DNS Lookup: What it is and How to Set it Up Reverse DNS maps an IP address back to a hostname. What rDNS is, how to run a lookup on Windows, macOS and Linux, and how to add the PTR record senders need. A 5-Minute Email Deliverability Check Before Hitting Send A 5-minute email deliverability check that catches spam triggers, auth failures, and provider-specific filtering. Full walkthrough with video and triage table. How to Fix Email Delivery Problems at Outlook Fix Outlook email delivery problems: diagnose authentication, reputation, technical, and compliance issues to land in the inbox instead of spam. Inbox for the Holidays: Proven Email Deliverability Tips Get your emails into the inbox this holiday season. Learn deliverability strategies from the “Inbox for the Holidays” webinar. How to Warm-Up Your Email and Domain for Trust Building Learn how to warm up your email and domain step by step to build sender trust, avoid spam folders, and improve deliverability. Top Reasons Why Your Emails Aren’t Being Delivered & Solutions Do you keep asking "why is my email not being delivered?" This guide inspects the most common email delivery issues and shows how to fix them What is a BIMI Record, and How do You Create One Learn what a BIMI record is, why it matters for email security, and how to create one step by step to display your brand logo in the inbox. SPF vs. DKIM: Key Differences Between The Two Explore SPF vs. DKIM: Key differences outlined to enhance your email security. Understand how these protocols work to protect your email from threats. DMARC vs. DKIM: Definition and Key Differences DMARC vs DKIM: what each record does, how they differ, and how they work together to authenticate your email and stop domain spoofing. How to Remove Your Email from Blacklists: A Step-by-Step Guide Learn the steps for email blacklist removal to restore your email deliverability, improve communication, and maintain a clean sender reputation. Adapting to Gmail and Yahoo’s Spam Protection Requirements Gmail and Yahoo's new sender requirements, effective February 2024, mark a major shift in email standards to combat spam and improve security. What Is a DMARC Record? Setup, Examples, and Why It Matters Secure your email domain with a DMARC record in 2024: Understand its importance in preventing spoofing and phishing for robust email security and trust. What Is a DKIM Record? How to Set It Up and Check It [2026] Enhance email security with a DKIM record: Learn what it is and how to set it up correctly to improve your email deliverability and protect against fraud. What Is an SPF Record? How to Create and Check One [2026] Unspam your emails with a correct SPF record. Learn the essentials of SPF records and get step-by-step guidance on creating one effectively. Why Domains Get Blacklisted: Causes, Signs and URI Blacklists Why a sending domain lands on a URI blacklist such as SURBL or URIBL, how domain listings differ from IP listings, and the signs that you have been listed.
![What Is a DKIM Record? How to Set It Up and Check It [2026]](/images/articles/dkim/dkim-cover.webp)
![What Is an SPF Record? How to Create and Check One [2026]](/images/articles/spf/spf-cover.webp)
