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Sendmarc makes it easy to achieve DMARC authentication. Our platform helps you publish the correct record, monitor authentication results, and enforce policies that block fraudulent emails, so only trusted senders can use your domain.
Protect your domain. Improve deliverability. Authenticate with confidence.
Domain-based Message Authentication, Reporting, and Conformance (DMARC) builds on two existing email authentication standards:
DMARC connects to these two by:
Together, SPF, DKIM, and DMARC create a layered email authentication strategy to prevent unauthorized use of your domain.
Without DMARC, your domain is exposed to email spoofing and phishing attacks. Cybercriminals can impersonate your brand to trick recipients into sharing sensitive data or downloading malware.
This can result in:
Book a demo with Sendmarc to protect your domain from fraud and improve your email performance.
DMARC checks the alignment of the domain in the email’s ‘From’ header against the domains authenticated by SPF and DKIM:
DMARC policies define how receiving email servers should handle messages that fail authentication checks:
Policy | Description | Use case |
---|---|---|
none | Monitor only. No impact on delivery. Reports are still generated. | Initial deployment and visibility into email sources. |
quarantine | Suspicious emails are sent to Spam or Junk folders. | Intermediate enforcement while monitoring results. |
reject | Messages that fail DMARC are blocked outright. | Fully protect your domain with strict enforcement. |
Start with p=none
to collect authentication data without affecting email flow. Once confident, gradually move to quarantine, then reject for stronger protection.
1. Create a DMARC DNS TXT record for your domain, including:
v=DMARC1
– Protocol versionp=
– Policy (none, quarantine, reject)rua=
– Email address for aggregate reportsruf=
– Email address for forensic reports (optional)pct=
– Percentage of emails subjected to policy (optional)2. Publish the DMARC record in your domain’s DNS.
3. Set up a dedicated email address to receive DMARC reports for monitoring.
4. Test and verify your DMARC configuration using online tools.
5. Analyze incoming reports to identify legitimate and unauthorized senders.
6. Adjust your DMARC policy from none to quarantine, then reject based on insights gained from reports.
DMARC authentication can fail for several common reasons:
If your domain is experiencing DMARC authentication failures, follow these steps:
Implementing DMARC effectively requires a strategic approach.
Here are the key best practices:
Ready to secure your domain?
Protect your domain from impersonation and improve your email deliverability with Sendmarc’s trusted DMARC authentication solution.
DMARC email authentication is a protocol that uses Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) to verify that emails are sent from authorized sources. It also instructs receiving email servers on how to handle messages that fail authentication checks.
DMARC authentication works by verifying SPF and DKIM results and checking if the domains authenticated by those protocols align with the domain in the email’s ‘From’ header. Based on the domain’s published DMARC policy, the receiving server will accept, quarantine, or reject the message if it fails authentication.
To pass DMARC verification, your emails must pass either SPF or DKIM checks, and the domain authenticated by the protocol must align with the domain used in the ‘From’ header of the email.
To set up DMARC authentication, first configure SPF and DKIM for all your sending services. Then create and publish a DMARC record in your domain’s DNS. Finally, monitor the reports generated to make ongoing adjustments and improve your protection.
To fix a DMARC authentication failure, verify that SPF and DKIM records are correctly configured and include all legitimate senders. Ensure the domains used for authentication align with the ‘From’ domain, and review DMARC reports to identify and address any issues. Update your DNS records as needed to resolve misconfigurations.
A “DNS authentication DMARC fail” message means that an email sent from your domain didn’t pass Domain-based Message Authentication, Reporting, and Conformance (DMARC) checks. This typically happens when the email also fails Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) validation, or when domain alignment is incorrect.