These are the response codes you can expect 98% of the times.
- 0: Message sent successfully to the wireless network operator
- 4: Message delivered to handset
- 3: Message buffered with carrier and waiting for a response, the status should change to 0, 4, or ESME_ROK eventually.
- 1070: Invalid phone number
- 1001: Blocked by Wire2Air Gateway. User is opted-out. In order to enable delivery, have user rejoin your campaign by texting a keyword to your assigned short code. If user opted-out in error and can't be joined by keyword, open a ticket with support to remove the block.
Status: 0 The Carrier acknowledgements which indicates delivery to the carrier, but does not mean that the destination handset actually received the message.
Status 4 is a Handset delivery receipts which indicates successful message delivery to the destination handset, but it's important to note that not all carriers support Handset delivery status.
You'll receive status 4 for carriers those who offer handset level delivery status reports. Not all carriers provide handset delivery reports. The USA carriers provide handset delivery reports are:
- Cincinnati Bell Wireless
- US Cellular
Rule of thumb: Delivery status 0, and 4 can be considered as "Message successfully delivered" and all others status are failed.
For rest of the carriers, you would either receive status "0" which means carrier has accepted the message successfully.
The lack of a handset acknowledgement does not imply that the message was not delivered to the subscriber, it just means that the carrier hasn't given us any acknowledgement.
Carrier may reject a message due to many reasons, and most of the times their error codes are ambiguous and that's why we can't provide a predefined set of response codes, these codes can changes time to time. There is no universal standard for these error codes, each carrier have their own set of errors.
On our end we have a logic to retry some of the failed messages via alternate route.
Since alternate route doesn't provide a reliable delivery reports, so we can't guarantee that message will be delivered. But based on our experience 90% of failed messages can be delivered via alternate route. These are two possible response code from alternate route:
delivered and undelivered.
For most part over all 98% of messages will be delivered without any issue. There might a failure for few smaller carriers' number, prepaid phones or if someone doesn't have text messaging enabled on their account.