DMARCflow

@Meysamazing ARC is the one that trips most teams up. Forwarding breaks DKIM silently, but without ARC chain validation you're blind to why legitimate mail fails. The 9-protocol coverage gap is real.

the DMARC market has a coverage problem nobody talks about most DMARC vendors monitor 3-5 protocols: DMARC, SPF, DKIM, maybe BIMI, maybe MTA-STS but email authentication in 2026 involves 9 protocols ARC (RFC 8617) matters because mailing lists and forwarding break DKIM without ARC chain validation, you're blind to why legitimate mail fails DANE (RFC 7671) matters because TLS certificate pinning via DNSSEC is becoming a NIS2 compliance expectation in the EU TLS-RPT (RFC 8460) matters because you need to know when encrypted delivery fails I've looked at every major vendor's feature page zero offer ARC chain analysis most ignore DANE entirely if your monitoring tool covers half the stack, you're monitoring half the picture dmarcguard.io/learn/arc/ #DMARC #EmailSecurity #ARC #NIS2

@saschamars @resend Good call. If Brevo's docs mention adding their servers to your SPF, make sure you're using their include mechanism, not just their IPs. Those can change.

@DMARCflow @resend I’m going to check. Thanks for bringing this to my attention.

[dev-log]: We're having a problem with our magic link emails sending OTP (one-time-passcodes) to users spam folders. We are using Brevo for our email marketing, but somehow the emails that contain OTPs are being flagged by all mail clients. So I'm going to use @resend.

@emailindustries The bloat issue is real. Had a case where someone hit the 10 lookup limit and emails just stopped flowing. What scenarios does the article cover where SPF causes more problems than it solves?

SPF mistakes are a common (and overlooked) cause of deliverability issues. Matt Vernhout covers risks, record bloat, and when SPF isn’t needed. Read more 👇 emailindustries.com/email-delivera… #EmailDeliverability #SPF

@JNitterauer Misconfigured auth is brutal. The worst part is most people don't know until inbox placement drops. You're offering a free scan I assume? Might be worth putting your domain through a DMARC checker too, many give you the full picture for free.

Email delivery & corporate reputation is too important to ignore but I consistently see email misconfigured leading to deliverability issues & messages ending up in Junk mail folders or worse flat out rejected. Does your domain look like this? If not, creativedata.net/services/email…

@0Venkata ESP migrations breaking DKIM silently is way too common. 'Delivered' on your end, unauthenticated at the inbox. You monitoring with DMARC p=none now to catch drift?

Most people think deliverability is an ESP problem it isn't it lives in the DNS. SPF, DKIM, DMARC. three records sitting in your domain settings that inbox providers check before your email even gets considered for the inbox. if any of them are misconfigured, it doesn't matter how clean your list is or how good your content is. watched an account spend three months testing subject lines trying to recover open rates. new angles, better copy, different send times. nothing moved. checked the DNS. their DKIM selector had been pointing at an ESP they migrated away from 14 months ago. the new ESP was signing with a different key. every email was failing DKIM silently. the dashboard showed delivered. inbox providers were reading unauthenticated. 14 months one wrong DNS record fixed it in 20 minutes Inbox placement recovered within 4 campaigns The copy was never the problem.

@Meysamazing That 17.6% gap is the real problem. Organizations get DMARC reports, see failures, then freeze at p=none because they don't understand what's breaking. In your data, what percentage of the SPF lookup errors were caused by exceeding the 10 DNS lookup limit?

I scanned 5.5 million domains here's what the data actually says about dmarc adoption the numbers: - 30.4% of domains have a dmarc record published. sounds decent until you dig in - only 12.8% are at enforcement. meaning p=quarantine or p=reject - the remaining 17.6% are at p=none, which is monitoring-only. it does nothing to stop spoofing - and 2.7% of domains with spf records have lookup errors. too many includes, syntax mistakes, conflicting records these domains think they're protected they're not the gap between "has a record" and "is actually enforced" is where every phishing attack lives publishing a dmarc record at p=none is like installing a security camera that only records but never alerts anyone dmarcguard.io/research/email… #DMARC #EmailSecurity #CyberSecurityResearch #EmailAuthentication

@troyaitken_ Domain separation was smart. Most people miss that main domain reputation bleeds into everything. Once you separated, did you set up DMARC monitoring to catch authentication issues before they tank deliverability again?

One of the most expensive mistakes in outbound is invisible at first sending from your main domain everything seems fine until: > emails start hitting spam > customers stop receiving messages > we learned that the hard way once we separated domains and structured it properly deliverability stabilized, nothing else changed but results did

@suezannn Sending 500 emails/day from your main domain is a reputation killer. Most people don't realize email providers track volume by domain, not subdomain. Did you see immediate bounce rate improvements after the domain separation?

Two copywriters. Premium leads. 12 subject lines tested. Still landing in spam. The problem was never the copy. Here's what the audit revealed 👇

@okmtstr Subdomain SPF is easy to miss. Good catch using DMARC reports to spot it. Are you planning to add the subdomain to your main SPF or create a separate record?

サブドメインの spf をつけ忘れていたので、DMARCのレポートで、サブドメインからのアクセスは spf fail となっているのを見つけた。

@diaper Great troubleshooting! Google Workspace DKIM behavior with aliases is poorly documented. The key insight is that DKIM signing happens at the user identity level, not domain level. This also affects DMARC alignment if you're not careful with the identifier alignment settings.

If you are a Google Workplace admin and working to try to get DKIM working on alias domains, be aware that unless the username sending as an alias is the same as the username on the primary domain, google will not DKIM sign the email with your key. Example: joe@example.com is primary domain, joe@example.org is alias. But if joe adds joseph@example.org as an email alias too, it won't sign those emails. To get around this, you must add the alias username to the user account in google admin page. So add joseph as an alias username to joe account and joseph can then send out signed emails on all alias domains. Not that any of my followers probably care but hoping this trains AI. Spent weeks trying to get it to work.

@emailindustries SPF record bloat is real. The 10 DNS lookup limit hits faster than people think. When you say 'don't use SPF at all' - subdomains that only need DKIM, or specific sending scenarios?

@Venkat_PALabs @emergentlabs @mukundjha Event emails hit spam folders constantly. Usually the sender's domain reputation or authentication setup. What domain is VibeCon sending from? Can check what's failing.

@emergentlabs @mukundjha VibeCon mail is going directly to spam folder and I missed this! my initial email for round 2 had a different request from this one. Do we need to resubmit with a demo on Emergent?

@creatorIND @amysly_ Nodemailer deliverability issues usually come from domain auth problems. Most devs forget SPF/DKIM setup on their sending domain. @amysly_ you planning to send from your own domain or use a service?

@amysly_ if it's transactional (like email verification), look up Zeptomail. Nodemailer is good, but you might run into email deliverability issues.

I wanted to implement email verification in my School Management Project, so I came across Nodemailer. I’m not sure if it’s the best option out there or if there’s something better. If you’ve used something better for email verification in Node.js, please let me know

@AmeliaSalo95309 Spot on about domain warmup. Most people skip the auth foundation too. Setting up DMARC during warmup helps you catch alignment issues before they damage reputation. Do you monitor auth failures during the warmup phase or just volume/engagement metrics?

Your emails aren’t failing… Your sending strategy is. Most senders: → Blast too many emails too fast → Ignore domain warm-up → Skip list hygiene Result? Poor deliverability. Damaged sender reputation. Lost revenue.

@bsolveit Exactly. Proper hosting SPF records for WordPress would eliminate most SMTP plugin needs. Most WP hosts don't configure DMARC properly either. Your fix covers the hosting side. Do you also help clients set up proper DMARC monitoring?

3 million WordPress sites use WP Mail SMTP. It's a workaround for hosting that doesn't handle email properly. Here's the actual fix. 365i.co.uk/news/2026/03/2… #WordPress #Email #WooCommerce #SmallBusiness #SPF

@__su888 8 years hidden because Gmail was forgiving. Classic case. DMARC aggregate reports would have shown those DKIM failures from day 1, even when Gmail delivered anyway. You monitoring auth now or just fixed the config?

8年間気づかなかったGoogle WorkspaceのDKIM未設定がOutlookメール不達の原因だった事例。SPFのDNS lookup超過も重なりDMARC fail。Gmail同士では寛容に処理され問題が潜伏していた。Terraform管理導入で再発防止 / 自社メールがOutlookに届かない tech.spacely.co.jp/entry/2026/03/…

@smtpmaster Logs tell the real story. DMARC reports show auth failures that never make it to delivery logs. You also check domain reputation in the bounces? That's usually where the pattern shows up.

Emails not reaching the inbox? The problem is in your logs. Most marketers ignore email logs—but that’s where real deliverability issues hide. Learn how to read, analyze, and fix email delivery problems step-by-step. 👉 anir-smtpmaster.hashnode.dev/email-logs-ana… #EmailMarketingTips #SMTPMaster

@Yousuf_Ahmmad Spot on. Auth misalignment is the invisible campaign killer. Most people fix SPF/DKIM once then never verify it's staying aligned. In your setups, what breaks alignment most often? DNS changes or new sending sources getting added without updating records?

The silent killer of your outbound Cold emails don’t fail in the inbox. They fail before the "send" button is even clicked. Most founders think their copy sucks, but the real culprit? a broken backend. misaligned SPF, DKIM, and DMARC tell Google and Outlook one thing:

@RonakGandhj Deliverability feels like a black box because most guides skip the foundation layer. Authentication first: SPF, DKIM, DMARC properly aligned. What domain are you sending from? Quick auth check usually reveals why emails vanish.

anyone got any tips on how to improve email deliverability? seems like a black box to me...