Errors

PTR Record Mismatch — Your Reverse DNS Is Wrong

A PTR mismatch means your IP’s hostname doesn’t round-trip to the same IP. FCrDNS fails — many servers junk or reject on that.

What FCrDNS means

Receiver does PTR on your IP → gets mail.example.com. Then A on mail.example.com must return your IP. Different IP → mismatch.

Your cloud or ISP — set rDNS in the panel (Hetzner, DO, AWS, etc.). Not your registrar’s MX screen.

Step 1 Run DNS Preflight with your sending IP → check PTR card

Step 2 Note the hostname PTR returns

Step 3 Check that hostname’s A record points back to your IP

Step 4 If mismatch → log into your hosting provider control panel

Step 5 Set reverse DNS to a hostname whose A points to your IP (e.g. mail.yourdomain.com)

Step 6 Add the A record if missing → re-run DNS Preflight

Run DNS Preflight with your sending IP

Also read: PTR record · Emails going to spam

PTR returns a hostname, but that hostname’s A doesn’t point back to your sending IP — FCrDNS fails.

Your host or ISP — not the domain registrar. Look for reverse DNS in the VPS panel.

Sometimes — more often it raises spam score.

A name you control — mail.yourdomain.com — with an A record to the same IP.

Propagation can take 24–48h. Double-check the A record for the PTR name.