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Posts tagged: dmarc

13 posts

20 min read

DMARCbis Is Published: RFC 9989, 9990, 9991 Replace 7489

DMARCbis is now Standards Track. RFC 7489 is replaced by RFC 9989, 9990, and 9991 (May 2026). What changed in policy records, tree walk, and reporting.

dmarcdmarcbisrfc-9989
19 min read

How to Read a DMARC Aggregate Report (XML Made Simple) [2026]

Read DMARC aggregate reports field by field. Annotated XML, Google vs Microsoft variants, and a live drawer demo. Free analyzer inside.

dmarcmonitoringemail-authentication
17 min read

What Is ARF in Email? Abuse Reporting Format

ARF (Abuse Reporting Format, RFC 5965) is the standard for DMARC forensic reports and email feedback loops. Annotated sample inside.

arfdmarcemail-authentication
13 min read

ARC Email Authentication: Forwarded Mail in 2026

ARC email authentication preserves SPF, DKIM, and DMARC verdicts across forwarding hops in 2026. See real i=1 and i=2 headers, cv=fail debugging, and trusted-sealer fixes. Analyze a chain free.

arcemail-authenticationdmarc
16 min read

Microsoft DMARC: Office 365 Setup Guide 2026

Microsoft enforces DMARC for Outlook senders since May 5, 2025. Set up DMARC for Office 365 and Microsoft 365 step-by-step with DNS examples. Configure now.

microsoft-365complianceemail-authentication
19 min read

Google, Yahoo & Microsoft DMARC Requirements

Google, Yahoo, and Microsoft now require DMARC for bulk senders — including Gmail's 2025 SMTP rejection escalation. See the full compliance checklist.

dmarccompliancebulk-sender
19 min read

DMARC Fails on Forwarded Emails: Why ARC Is the Fix

Forwarded emails fail DMARC because SPF breaks in transit. See why, when DKIM survives, and how ARC seals the chain across every forwarding hop.

dmarcarcforwarding
19 min read

SPF Flattening: Fix Too Many DNS Lookups (2026)

148,655 domains exceed the SPF 10-lookup limit. Learn what SPF flattening is, when to use it, 4 safer alternatives, and step-by-step fixes. Check free.

spftroubleshootingemail-authentication
18 min read

SPF Softfail vs Hardfail: Which to Use?

53.6% of domains use SPF softfail, 40.2% use hardfail. Learn how each qualifier works, how DMARC changes the equation, and which to choose. Check your SPF free.

spfemail-authenticationdmarc
23 min read

SPF PermError: How to Find and Fix It (2026 Guide)

SPF PermError breaks DMARC alignment and kills deliverability. Learn the 5 causes, step-by-step fixes, and platform-specific examples. Check your SPF free.

spftroubleshootingemail-authentication
20 min read

DKIM Fail: How to Fix Alignment and Verification Errors

DKIM failing? Learn why DKIM alignment breaks, how to fix body hash errors, and how to configure third-party senders. Step-by-step guide with CLI commands.

dkimtroubleshootingemail-authentication
15 min read

DMARC Quarantine/Reject Policy Not Enabled: Fix It

See 'DMARC quarantine/reject policy not enabled'? Learn what it means, why it matters, and how to fix it step by step for any DNS provider. Free checker included.

dmarctroubleshootingemail-authentication
29 min read

DMARC Fail: 7 Causes & How to Fix Each (2026 Guide)

DMARC failed? Fix it fast: 7 causes (SPF/DKIM misalignment, third-party senders, forwarding) with diagnose steps, fixes, and a free DMARC checker.

dmarctroubleshootingemail-authentication