null_mx
The domain declares that it never accepts mail
The domain publishes a null MX record, the standard way of saying it does not receive email.
- appears in
- reason
- verdict
- undeliverable
- credits
- Free. Undeliverable verdicts never cost a credit.
What it means
RFC 7505 lets a domain publish a single MX record pointing at "." with priority 0, the null MX, to state explicitly that it does not receive email. Website-only domains, brand-protection domains and parked domains use it.
It is a deliberate, authoritative statement, so Spaw does not try the address-record fallback and does not probe. mx_found is false.
What to do
Reject the address. There is no correction to suggest, and nothing changes unless the domain owner removes the record.
Example response
{
"email": "[email protected]",
"deliverable": "undeliverable",
"reason": "null_mx",
"mx_found": false
}Abbreviated: a real answer carries all 27 fields, listed in the verify-email reference.
Related
- invalid_syntax · the input does not parse as an email address
- invalid_local_part · the username breaks the rules its own provider enforces
- no_mx_records · the domain has no mail servers at all
- mx_unresolvable · the mail servers the domain points at do not exist
- mailbox_not_found · the mail server rejected the mailbox during the handshake
- mailbox_disabled · the mailbox exists but its provider has disabled it
- suppressed · the address is on your account's suppression list
- All verdict reasons
- Verdicts and the risk score
- API reference
markdown version: /docs/reasons/null_mx.md