DLR Error Code 9 Illegal Number DLR Error Code 9 Illegal Number

DLR Error Code 9 Illegal Number

Nexmo Support

Question

What does it mean when I see a delivery receipt error code 9 in response to my outbound SMS?

Applies To

  • Outbound SMS
  • Error Code 9
  • Blacklisted Numbers

Answer

Error code 9 Illegal Number refers to messages sent to a blacklisted number where the user has explicitly requested to STOP receiving messages from a particular service.