DMARC (Domain-based Message Authentication, Reporting & Conformance) is a critical email authentication protocol that helps prevent your emails from being marked as spam or phishing. If your DMARC record is misconfigured, your emails may never reach the inbox. This guide shows you how to diagnose and fix DMARC issues step by step so your emails get delivered every time.
What is DMARC and Why Does It Matter?
DMARC builds on SPF and DKIM to give domain owners control over how unauthenticated emails are handled. A correct DMARC setup protects your brand, improves deliverability, and helps prevent spoofing and phishing attacks. Without DMARC, your emails are more likely to be flagged as spam or rejected by major providers.
Common DMARC Errors That Hurt Deliverability
1. No DMARC Record Published
If you don't have a DMARC record in your DNS, your domain is vulnerable to spoofing and your emails may be rejected or sent to spam.
2. Syntax Errors in the DMARC Record
Even a small typo can break your DMARC record. Common mistakes include missing semicolons, incorrect tags, or invalid values.
3. Policy Not Strict Enough (p=none)
A DMARC policy of p=none only monitors but doesn't protect. For full protection, use p=quarantine or p=reject once you're confident in your setup.
4. SPF or DKIM Misalignment
DMARC requires that either SPF or DKIM "aligns" with the domain in the From address. If not, DMARC will fail even if SPF/DKIM pass individually.
5. Missing or Incorrect rua/ruf Tags
The rua and ruf tags specify where to send DMARC reports. Incorrect addresses or syntax can prevent you from receiving valuable feedback.
Step-by-Step: How to Fix DMARC Record Issues
1. Check for an Existing DMARC Record
Use a DMARC lookup tool or check your DNS to see if a DMARC record exists for your domain. The record should be at _dmarc.yourdomain.com.
2. Validate the Syntax
Use online DMARC validators to check for typos or formatting errors. A valid DMARC record looks like: v=DMARC1; p=quarantine; rua=mailto:you@yourdomain.com
3. Align SPF and DKIM
Make sure your SPF and DKIM records are set up and that at least one aligns with your From domain. This is required for DMARC to pass.
4. Set an Appropriate Policy
Start with p=none to monitor, then move to p=quarantine or p=reject for full protection once you're confident.
5. Add rua/ruf Tags for Reporting
Specify valid email addresses for aggregate (rua) and forensic (ruf) reports so you can monitor authentication results and spot issues quickly.
6. Publish the Record in DNS
Add or update your DMARC record in your DNS provider’s dashboard. Changes may take a few hours to propagate.
How to Test and Monitor Your DMARC Setup
- DMARC Lookup Tools: Use online tools to check your DMARC record and get instant feedback on errors or misconfigurations.
- Monitor Reports: Review DMARC aggregate and forensic reports to spot authentication failures and unauthorized senders.
- Check SPF/DKIM Alignment: Use email testing tools to verify that your SPF and DKIM records align with your From domain.
The Future of DMARC and Email Authentication
- Stricter Enforcement: Major providers are increasingly requiring DMARC for deliverability. Expect more domains to move to
p=rejectpolicies. - Automated Tools: New tools are making it easier to set up and monitor DMARC, SPF, and DKIM records—even for non-technical users.
- Greater Transparency: DMARC reporting is helping organizations spot abuse and improve their email security posture.
Take Action: Fix Your DMARC Records Today
Don’t let DMARC issues keep your emails out of the inbox. Use this guide to diagnose and fix your DMARC records, improve deliverability, and protect your brand from spoofing and phishing.
Need help fixing your DMARC records? Test your setup and get instant feedback on your configuration to protect your domain and boost your deliverability today.