SpamAssassin rule
NML_ADSP_CUSTOM_LOW
Missing signature from a domain that always signs
+0.7 points
Combination of other tests (meta rule)
What NML_ADSP_CUSTOM_LOW means
The From domain is one that SpamAssassin knows signs all its mail with DKIM (mostly banks, payment and shipping companies and big webmail providers), but this message has no valid signature from it.
The rule's description in SpamAssassin: “ADSP custom_low hit, and not from a mailing list”
How to fix it
Send mail for such a domain only through its own servers. If it is your domain, sign every message with DKIM using your domain.
Does your email trigger NML_ADSP_CUSTOM_LOW?
Send it to a free test address: we run SpamAssassin, check SPF, DKIM and DMARC and show every rule with a fix.
Open the email spam checkerRelated rules
ARC_INVALIDARC signature is invalid
DKIM_ADSP_ALLDomain says it signs all mail, but this message is unsigned
DKIM_ADSP_DISCARDDomain asks to discard unsigned mail
DKIM_ADSP_NXDOMAINFrom domain does not exist
DKIM_INVALIDDKIM signature is invalid
DKIM_SIGNEDMessage is DKIM-signed
DKIM_VALIDValid DKIM signature
DKIM_VALID_AUDKIM signature from your own domain
DKIM_VALID_EFDKIM signature from the envelope sender's domain
Frequently asked questions
What does NML_ADSP_CUSTOM_LOW mean?
The From domain is one that SpamAssassin knows signs all its mail with DKIM (mostly banks, payment and shipping companies and big webmail providers), but this message has no valid signature from it.
How do I fix NML_ADSP_CUSTOM_LOW?
Send mail for such a domain only through its own servers. If it is your domain, sign every message with DKIM using your domain.
How many points does NML_ADSP_CUSTOM_LOW add?
0.7 points in the default SpamAssassin ruleset (network tests on, Bayes off). A message is treated as spam from 5.0 points. Mail servers can change scores locally.