Video transcript

1. 00:00Intro

   Here is how to read a DMARC record, and how to build one without guessing the tags. DMARC tells receivers what to do with mail that fails SPF and DKIM checks against your From domain. The DMARC Checker reads your live record, with no signup. You only enter the domain. The checker looks at _dmarc.yourdomain. That host matters. A DMARC record at the domain root does nothing. Enter the domain, and click Check DMARC.

2. 00:30Read the DMARC record

   The record is live, so let's read the tags. p=none is monitor mode. Receivers take no action on failing mail. rua is where aggregate reports go. Without it, you learn nothing, and you can't tighten the policy safely.

3. 00:45DMARC Generator

   To publish or change a record, use the second tool, the DMARC Generator. Every tag has its own field: policy, subdomain policy, percentage, report addresses and alignment. Enter your domain, then pick a policy. None only monitors. Quarantine sends failing mail to spam. Reject blocks it. This example uses quarantine. Add an address for aggregate reports, and generate the record.

4. 01:11Publish and roll out

   The record comes back with its host and its full value. Publish it as a TXT record at _dmarc.yourdomain. Roll it out in stages. Start at p=none with a report address, and read the reports. Then move to quarantine, then reject. DMARC only reads SPF and DKIM results. With neither set up, this record does nothing. When it's live, run the checker again.

5. 01:35Get started free

   20 free credits every day you use your account, up to 600 a month. No credit card required. Start at billionverify.com.

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