The error code 0x00000066 translates to “ESME_RECEIVER_REJECT_MESSAGE” in the context of Short Message Service (SMS) protocols. This error indicates that the Short Message Service Center (SMSC) rejected your SMS message.

Here’s a breakdown of the causes, solutions, and additional resources:

Causes:

• Invalid Message Content: The SMSC might have rejected your message because it contains invalid or prohibited content. This could include restricted characters, spam triggers, or content exceeding character limits set by the network operator.
• Destination Number Issues: The recipient’s phone number might be invalid, non-existent, or blacklisted by the network operator.
• Insufficient Credit or Service Issues: Your mobile plan might not have sufficient credit or lack the necessary features (e.g., international SMS) to deliver the message to the recipient’s network.
• SMSC Configuration: In rare cases, specific configurations on the SMSC itself might be causing it to reject certain types of messages.

Solutions:

Here are some steps you can take to address the 0x00000066 error:

1. Review Your Message Content: Double-check your message for any typos, special characters, or content that might violate your network operator’s SMS guidelines.
2. Verify Recipient Number: Ensure you have entered the recipient’s phone number correctly and that it’s a valid, active number.
3. Check Your Mobile Plan: Review your mobile plan details to confirm you have enough credit or the necessary features for sending SMS messages, especially if sending internationally.
4. Contact Your Mobile Network Operator: They might be able to provide more specific information about the reason for the rejection and offer potential solutions.
5. Edit and Resend: If it’s a content-related issue, try editing your message to comply with the guidelines and resend it.

Additional Considerations:

• The specific reason for rejection depends on the network operator and the configuration of the SMSC.
• By following these steps, you can potentially identify the cause and rectify the issue to successfully send your SMS message.

Additional Resources:

• SMPP Error Codes – OpenMarket: https://www.openmarket.com/docs/Content/apis/v3smpp/smpp-om-error-codes.htm
• SMPP Error Codes – SMSC Server Library – Tops: https://www.openmarket.com/docs/Content/apis/v3smpp/smpp-om-error-codes.htm

Remember, encountering the 0x00000066 error doesn’t necessarily mean your message is malicious. By reviewing the content, recipient number, and your mobile plan, you can often resolve the issue and get your message delivered.