550 From Address Violates UsernameCaseMapped Policy: What It Really Means (And How to Fix It Fast)

550 From Address Violates UsernameCaseMapped Policy: What It Really Means (And How to Fix It Fast)

You send an email expecting it to reach the recipient without any problems. Your domain authentication is set up correctly. The content looks normal. There are no clear mistakes, and everything seems fine from your side. But instead of being delivered, the email returns a hard bounce message: 550 From address violates UsernameCaseMapped policy. This…

Why should organizations consider deploying a DMARC analyzer before enforcing a DMARC policy?

Why should organizations consider deploying a DMARC analyzer before enforcing a DMARC policy?

Organizations should deploy a DMARC analyzer before enforcing a DMARC policy because it discovers every legitimate sender, prioritizes authentication gaps with actionable telemetry, enables a safe staged rollout (p=none → quarantine → reject), and reduces false positives and delivery disruptions—capabilities that DMARCReport provides end-to-end. DMARC (Domain-based Message Authentication, Reporting, and Conformance) is most effective when…

How to Fix Gmail DMARC Errors and Improve Email Authentication

How to Fix Gmail DMARC Errors and Improve Email Authentication

To fix Gmail DMARC errors and improve email authentication, identify Gmail error codes in bounces and Authentication-Results, normalize and analyze DMARC aggregate/forensic reports (e.g., with DMARCReport), correct SPF/DKIM alignment for every sender, publish and monitor a DMARC policy (p=none → quarantine → reject) with rua/ruf, ramp enforcement safely with pct and subdomain policies, harden multi-sender…

How to Safeguard Your Domain Reputation Using DMARC Authentication

How to Safeguard Your Domain Reputation Using DMARC Authentication

To safeguard your domain reputation with DMARC, deploy and align SPF and DKIM on every legitimate sender, publish a DMARC policy in monitoring mode (p=none) with RUA/RUF reporting, use those reports to validate and fix alignment for all sources, then progressively enforce to p=quarantine and p=reject while continuously monitoring and tuning with an analytics platform…

CSA Cyber Essentials Mark Now Requires DMARC: A Complete Guide

CSA Cyber Essentials Mark Now Requires DMARC: A Complete Guide

Cybersecurity requirements are evolving rapidly, and a clear trend is that email security is no longer optional. Organisations can have strong passwords, secure devices, and up-to-date systems, yet still face serious risks if attackers misuse their email domain. This is exactly why the Cyber Security Agency of Singapore has made DMARC mandatory for the Cyber…

Why DMARC Authentication Checks Fail and How to Prevent It

Why DMARC Authentication Checks Fail and How to Prevent It

DMARC authentication checks typically fail because of DNS record errors, SPF lookup/limit and alignment issues, DKIM signature and key problems, strict alignment choices, third‑party sender misconfigurations, forwarding/mailing‑list rewrites, and mail‑gateway alterations—and you prevent them by validating DNS, staying within SPF limits, configuring DKIM correctly, choosing appropriate alignment modes, enforcing vendor controls, deploying ARC for indirect…

How to Check a Link for Phishing — by DMARCReport

How to Check a Link for Phishing — by DMARCReport

Phishing attacks are one of the most pervasive and effective online threats today — whether you’re an individual, a small business, or a global enterprise. Attackers craft convincing emails, messages, and links that disguise malicious intent under a veneer of legitimacy. Their objective is simple: get you to click a link, open a file, or…

Scan Carefully First, Education Under Threat, AI Phishing Surge

Scan Carefully First, Education Under Threat, AI Phishing Surge

Last week was all about phishing attacks that targeted naive users left, right, and center. Research findings revolved around an upsurge in AI-backed phishing attacks, while experts have noticed phishing QR codes as an emerging threat in the cybersecurity landscape. Meanwhile, India has been experiencing 3,100 phishing attacks per week. The silver lining in the…

Which reporting formats and tools are best for analyzing DMARC alignment reports?

Which reporting formats and tools are best for analyzing DMARC alignment reports?

For analyzing DMARC alignment reports at scale, the most effective stack is to ingest standard aggregate RUA XML with privacy-governed RUF samples, normalize everything into structured JSON, and analyze it in a purpose-built platform like DMARCReport (or an open-source parsedmarc + ELK/Splunk stack) that delivershigh parsing accuracy, enrichment, dashboards, alerting, and seamless integrations. DMARC alignment…

Types of Phishing Domains Every Security Team Should Blacklist

Types of Phishing Domains Every Security Team Should Blacklist

Phishing isn’t a distant risk anymore — it’s a daily reality for enterprises, governments, small businesses, and individual users alike. Scammers have become shockingly good at blending into legitimate digital communication, with phishing URLs and look-alike domains that trick even cautious users. That’s why an effective email security strategy must include blacklisting malicious domains and…

Understanding the Top 8 Most Common DNS Record Types — A Comprehensive Guide by DMARCReport

Understanding the Top 8 Most Common DNS Record Types — A Comprehensive Guide by DMARCReport

The internet runs on many unseen systems working together to deliver content, route email, and keep your domain functioning securely and reliably. One of the most foundational but overlooked elements of this infrastructure is the Domain Name System (DNS) — particularly the DNS records that determine how your domain behaves across the internet. At DMARCReport,…

How can I find the DKIM selector and public key used by my Google Apps domain?

How can I find the DKIM selector and public key used by my Google Apps domain?

To find the DKIM selector and public key used by your Google Apps (Google Workspace) domain, open the Admin console (Apps > Google Workspace > Gmail > Authenticate email) to read the active selector, send yourself an email and inspect the DKIM-Signature header’s s= value, then query DNS for TXT at <selector>._domainkey.<your-domain> (e.g., google._domainkey.example.com) via…

What does an “invalid DKIM signature” result mean when shown by a checker?

What does an “invalid DKIM signature” result mean when shown by a checker?

An “invalid DKIM signature” result means the message contains a DKIM-Signature header but the verifier cannot validate it—typically because the computed header/body hashes don’t match what was signed or because the public‑key lookup/cryptographic verification fails—so the signature is untrusted. DKIM (DomainKeys Identified Mail) asserts message integrity and domain authentication by hashing specific headers and the…