TrueDialog Portal
Knowledge
When viewing a Message Log generated from the Requested Reports page, you can include delivery codes based on DLR (Carrier Delivery Receipt). A DLR is an acknowledgment from a destination carrier network that a message was successfully accepted or rejected (including the reason for rejection).
There are two types of DLRs: Intermediate and Handset.
What is an Intermediate DLR?
An intermediate DLR means the end carrier has received the message, and it’s usually considered successful. In the US and Canada markets, ACCEPTED (SMPP 3.4) will be the most precise indicator of a successful message for local long-codes. Specifically, on Local A2P and Local P2P messaging, you will only see intermediate DLRs supported.
Even after sending back an acknowledgment, some carriers may be unable to deliver the message due to downstream spam filters or other reasons. If True Dialog receives a clear rejection for a message, you’ll always see a failed delivery status reflected.
Even though intermediate DLRs don’t represent actual final delivery to a handset, knowing that the message was received at some point along the delivery path to your customer’s handset can help with troubleshooting when customers are not receiving messages.
What is a Handset DLR?
A Handset or Final DLR confirms that your message was delivered to the recipient’s handset and will be returned to TrueDialog as DELIVERED (SMPP 3.4).
Depending on the carrier, handset DLRs are only possible for A2P traffic on toll-free numbers and short-codes. Carriers only provide intermediate or carrier DLRs for all P2P and A2P long-code routes in the US and Canada. The downstream page is ultimately responsible for returning a DLR in response to a request for one. If a carrier does send a final DLR, the status will be updated within the portal and reporting.
Common Undelivered Codes and Definitions
| Code | Description |
|---|---|
| DB76 | Subscriber profile does not permit the service |
| DB78 | Billing No Balance (Insufficient credit) |
| 450D | You have reached the maximum number of messages allowed |
| DB99 | Unknown or Ported Number |
| 4503 | No operator found for current MSISDN |
| 4524 | MSISDN has been blocked on end-user request OR has been filtered on customer request |
| 4503 | No operator found for current MSISDN |
| DB52 | Rejected by operator |
| DB62 | Rejected by operator or Out of Coverage |
| DB65 | Message Expired (Validity Period Expired) |
| DB05 | ‘Call barred by destination operator’, or ‘Rejected by destination operator’ |
| DBF6 | SMS MT has been rejected by operator. User must send MO to unblock messages |
| 002 | Expired |
| 187 | Spam Detected – Statistical |
| 188 | Spam Detected – Keyword |
| 189 | Spam Detected |
| 406 | Rejected – Unallocated To Number |
| 482 | Loop Detected |
| 600 | Destination Carrier Queue Full |
| 610 | submit_sm or submit_multi Failed |
| 620 | Destination App Error |
| 630 | NACK |
| 700 | Invalid Service Type |
| 720 | Invalid Destination Address |
| 740 | Invalid Source Address |
| 750 | Destination Rejected Message |
| 770 | Destination Span Detected |
| 771 | Rejected – Shortened URL |
| 772 | Rejected – Telephone Number Blocked |
| 775 | Destination Rejected |
| 780 | Volume Violation – T-Mobile |
| 781 | p2p Volume Violation |
| 785 | Volumetric Violation |
| 999 | Unknown Error |