No DMARC record
Nothing published at _dmarc.yourdomain, so anyone can spoof the domain and you receive no reports about it.
What causes it
- No record was created, or it was published on the domain root instead of the _dmarc subdomain.
How to fix it
Publish a TXT record at _dmarc.yourdomain — not on the domain itself. Start with v=DMARC1; p=none; rua=mailto:you@yourdomain and read the reports for a few weeks before enforcing.
Check your domain
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