5 Email Authentication Edge Cases Basic SPF/DMARC/DKIM Checkers Miss
Five real SPF, DMARC, and DKIM edge cases, shown on public domains, that shallow email security checkers report as passing, and how to catch them.
Erich Kolb
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Strategy, security, and operational guidance for growing small businesses and solo founders.
Two New Free Tools: SPF & DMARC Generator and Password Breach Checker
Generate correct SPF and DMARC DNS records in seconds, and check whether any password has appeared in a data breach, without ever sending the password to a server.
Erich Kolb
Free IT Diagnostic Tools: DNS, SSL, Email Security, and HTTP Headers
Free DNS checker, SSL certificate inspector, email security validator (SPF, DMARC, DKIM), and HTTP headers analyzer. No account, no install, instant results from your browser.
Erich Kolb
How to Stop Burning Tokens in Claude Code: Practical Ways to Reduce Costs and Extend Your Usage
A practical guide to Claude Code token optimization, including context management, cost reduction strategies, and proven techniques to conserve API credits.
Erich Kolb
What the New Email Authentication Requirements Mean for Your Domain
Google and Yahoo now require DMARC, SPF, and DKIM for all senders. If your domain is not configured correctly, your email lands in spam or gets rejected outright.
Erich Kolb
How to Spot LinkedIn Recruitment Scams Before They Become a Security Incident
LinkedIn recruitment scams look like real job offers. Learn the warning signs, the common patterns, and how to stop one from becoming a security incident.
Erich Kolb
MFA Is Not Enough: Protecting Against Session Token Hijacking
Attackers can bypass MFA by stealing session tokens. Learn how session hijacking works and the layered defenses that stop account takeovers.
Erich Kolb