Domain-based Message Authentication, Reporting, and Conformance (DMARC) is a mechanism for improving mail handling by mail-receiving organizations. The ultimate purpose of DMARC, according to RFC-7489 is to provide a “mechanism by which email operators leverage existing authentication and policy advertisement technologies to enable both message-stream feedback and enforcement of policies against unauthenticated email. Email originating organizations utilize DMARC in order to express domain-level distribution policies/preferences for message validation, disposition, and reporting.

How DMARC Works:

DMARC adoption has risen dramatically and has a positive or negative impact on your email deliverability. All of the major email providers support DMARC. By some measures, 80% of mailboxes worldwide are protected by DMARC.

DMARC dramatically improves on SPF and DKIM by letting you:

Monitor, detect and fix real world problems with your SPF and DKIM configuration
See the email volumes you’re delivering to inboxes
Identify threat emails pretending to come your domain. (Spoofing)
Control the delivery of your email and defend against spoofing attacks.

How do I set it up?

It only takes a few minutes to get started with DMARC and you’ll see immediate benefits. The first thing you need to do is add a simple DNS record to enable DMARC reporting. If you would like MxToolBox to handle your DMARC reporting for you, just add this simple text (TXT) record to your domain’s DNS.

Setup DMARC Deliverability Report

What is DMARC Authentication?

To pass DMARC authentication, a message must both Pass and Align for either SPF or DKIM. Even if a message passed authentication for both SPF and DKIM, it could still fail DMARC authentication if one of them does not “align.” There are two ways to pass DMARC authentication:

SPF Passes, meaning the message was delivered from an IP address published in the SPF policy of the the SMTP envelope “mail from:” (mfrom) domain, and also

SPF Aligns, meaning the <From:> header visible to the end user matches the domain used to authenticate SPF. (e.g. the envelope “mail from:” domain)

-OR-

DKIM Passes, meaning the message was correctly signed by the d= domain in the DKIM header, and also

DKIM Aligns, meaning the <From:> header visible to the end user matches the d= domain in the DKIM header.

What is alignment again?

When a message is aligned, the end user recipient knows who really sent the message.

SPF and DKIM are only authentication mechanisms. Passing SPF or DKIM authentication only means the receiving organization can identify the real sending domain. But typically, the end user receiving the message never sees this domain. Instead, they see the “From:” address in the email header.

So it’s possible for a message to pass both SPF and DKIM authentication, but still trick the end user to thinking it came from someone else (i.e. spoofing). When a message is aligned, the friendly domain visible in the email client matches the domain used to authenticate with SPF or DKIM.

What DMARC Policy should I publish?

If a message fails DMARC authentication, the receiving organization should honor the “disposition” you publish in your DMARC policy. This is the p= value in your DMARC record:

p=none	Take no action other than sending aggregate reports. This let’s you see which messages are failing DMARC and fix the problems. With reporting enabled, you will get reports from organizations all over the world, including all of the big mail providers like Google, Yahoo, and Hotmail.
p=quarantine	Once your DMARC compliance is high enough, you may direct receiving organizations mark messages failing DMARC as spam. You’re telling the world your SPF and DKIM deployment is very accurate and to be careful with any message that fail.
p=reject	Once you’re sure all of your important messages are passing DMARC, you may direct organizations to outright reject messages that fail. You’re telling the world your SPF and DKIM deployment is fully complete and up to date.

DMARC is the key to improving Email Deliverability!

Email is the key to your customer communication strategy. But, what is your email reputation?

Setting up and managing your DMARC configuration is the key to getting insight into your email delivery. MxToolbox is the key to understanding DMARC.

MxToolbox Delivery Center gives you:

Who is sending phishing email purporting to be from your domain
What is the reputation of your domains and delegated IPs
Where other senders are and What their reputations are
How your SPF, DKIM and DMARC setup is performing
What on-going maintenance you need to maintain and improve your email deliverability

Learn More

DMARC Record Published

More Information About Dmarc Record Published

If you are encountering this error of No DMARC Record found, this means that your domain does not have a published DMARC record. DMARC Records are published via DNS as a text(TXT) record. They will let receiving servers know what they should do with non-aligned email received from your domain.