How to Protect Your Domain with DMARC

The Warmup Inbox Team
The Warmup Inbox Team

What Is DMARC?

Domain-based Message Authentication, Reporting, and Conformance (DMARC) is a DNS protocol that utilizes the Sender Policy Framework (SPF) and Domain Keys Identified Mail (DKIM).

DMARC helps Internet Service Providers authenticate incoming and outgoing email messages originating from a specific domain. Verifying the validity of a message ensures that spam, spoofed, malicious, or illegitimate mail doesn’t make it into consumer inboxes.

DMARC functions as an extension of the two existing email authentication protocols. It enables a domain user to publicly publish a policy in their DNS records that specifies which protocols to implement when receiving a message. This record also indicates how the server should handle rejected or malicious messages, clarifying whether the message should be bounced back to the sender or redirected to another inbox for quarantine.

Authenticating your email with DMARC allows ISPs to verify that your email is sent by you rather than someone pretending to be you. DMARC uses SPF to validate that the message is coming from you and DKIM to confirm that it hasn’t been tampered with since it left your server.

DMARC also provides you with feedback that helps you understand why certain emails cannot be delivered so you can improve your sending practices.

Why Is It Important to Protect Your Domain Reputation?

Protecting your domain reputation is a critical part of email deliverability. The higher your reputation is, the more likely it is that ISPs will let your message through to their clients. So maintaining your reputation is pretty important if you want to make the most of your email campaigns.

There isn’t one single way to protect your domain reputation. Since your reputation is the sum of many parts, you have to juggle multiple components. The good news is that as long as you practice safe sending habits and good email etiquette, you should have no issues with keeping your reputation strong.

However, if your account is compromised, your reputation can pay the price. If a hacker starts sending out random emails with phishing links on your behalf, your domain can get placed on a blocklist.

How Does DMARC Help to Protect Your Reputation?

DMARC validates that a message is legitimately coming from you, protecting your reputation from being damaged by cybercriminals.

Whether the email you send is being sent to potential or to current subscribers, mass email campaigns can be a highly effective way to move people through your sales funnel. However, mass email marketing can come with problems if you don’t stay on top of your reputation. If your sender reputation is neglected, you could end up getting multiple spam reports and potentially have your domain placed on a blocklist.

Having a DMARC record for your domain lets ISPs know that you’re doing your part to ensure good sending habits. Publishing a DMARC record allows your domain to receive feedback about your email authentication so you can improve your email authentication with SPF and DKIM.

ISPs automatically trust DMARC-authenticated senders and are more likely to let messages from them through to the recipient. Since having a DMARC record shows that you’re putting in the effort to establish a secure domain that isn’t trying to harm the recipient, ISPs trained to weed out spam and malicious content will realize that you’re a safe sender.

In short, a DMARC record improves email deliverability by helping the recipient validate the security of the message. This way, you get more messages into people’s inboxes instead of their spam folders.

Of course, a DMARC record isn’t like having the Wizard of Oz grant you entry to inboxes or remove your domain removed from a blocklist. If that were the case, spammers would simply set up a DMARC record and call it a day. Your DMARC record is more like one of the steps on the Yellow Brick Road to a positive reputation and high deliverability. Every little bit you do to show that you’re working to keep consumers safe helps.

What Is the DMARC Policy?

A DMARC policy enables domain owners to show that their messages are protected through SPF and DKIM. The policy also informs the recipient what they should do if an incoming message doesn’t have these verifications attached. If an email arrives without authentication, then the receiving server will know whether to send it to the junk folder or bounce the message altogether.

You can set your DMARC policy with a couple of commands to tell servers how to handle unverified messages:

  • Monitoring (p=none): Doesn’t have an impact on mail flow and sends feedback to the sender
  • Quarantine (p=quarantine): messages that fail DMARC are moved to the spam folder
  • Reject (p=reject): messages that fail DMARC are bounced back to the sender

For your email to be DMARC compliant, the domain the message is from must match the domain validated through SPF or the valid DKIM signature. Think of it as two-factor authentication for your emails.

As long as your email matches at least one of your SPF or DKIM registrations, then your message will be verified as legitimate.

Common DMARC Issues and How to Fix Them

Problems with your DMARC record can impact ISP’s ability to verify your domain address. Here are some of the most common issues and how to get them fixed

Problem: you left out the v=DMARC1 tag or typed in “v=dmarc1”

Solution: check your record and ensure that you have “v=DMARC1” entered at the beginning of the record exactly like that


Problem: you have missing or incorrect characters

Solution: check that your command was typed in correctly without any extra or missing characters (including spaces) that would throw off the command


Problem: you leave your record at p=none for an extended period of time

Solution: The p=none request puts your domain into monitoring mode. If you want to protect against spoofing, then you have to move the command to p=reject or p=quarantine.


Problem: you set a pct= tag at less than 100%

Solution: If you have p=quarantine and your percentage is less than 100, there’s a chance that some spoofed emails could slip through the cracks. By default, DMARC sets pct at 100, so there’s no need to add a pct tag if you haven’t added one yet. But if you do have one, move it back to pct=100.


Problem: you didn’t set different parameters for subdomains

Solution: Your default settings will automatically be applied to your subdomains. But you still have to bring your subdomains into DMARC enforcement by adding the tag “sp=none.” This will ensure that your subdomains can’t be spoofed.


Problem: you aren’t using the correct DMARC syntax

Solution: Check that your tags are in the right order. You can use an online application to make sure that everything is arranged to work as requested.


Problem: you didn’t specify a reporting address

Solution: add a “rua=” tag to let DMARC know where to send reports about messaging


Problem: your SPF or DKIM records aren’t configured correctly

Solution: check your SPF and DKIM registrations to make sure they’re correct and match the domain for your DMARC policy

Using Warmup Inbox to Protect Your Domain Reputation

Once you’re ready to go with DMARC, there are a variety of steps you can take to maintain a positive domain reputation. Our platform allows you to warm up your inbox, keep it warm, and monitor the health of your inbox. The best part? You don’t have to do anything.

Try it free today and discover what Warmup Inbox can do for you.

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