Common Message/SMS Errors

Messages may fail on occasion, here are some common errors that we see or experience.

Every message in Whistle has a delivery status report. Most of your messages will be Delivered, but on occasion, an SMS will fail to send and provide you with an Error message.

Here are the most common problems we see:

"Message Delivery - Unknown error": The recipient's carrier has returned a generic error message.

"Message Delivery - Unknown destination handset": The recipient carrier is reporting the To number is unknown, or no longer in service.

"Message Delivery - Unreachable destination handset": The recipient carrier is reporting the 'To' number is unreachable - the device is likely powered down, out of the service area, or may not accept your messages.

"Message Delivery - Carrier Violation": The recipient's carrier is filtering out your messages for delivery.

"Message Delivery - Message blocked": Your message has been blocked from reaching the recipient by the carrier.

"Message Delivery - Landline or unreachable carrier": The recipient's number is a landline phone, or the recipient carrier can't be reached.