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Preventing Message Filtering by Carriers (Error 30007)

Message filtering occurs when carriers block messages deemed unwanted or illicit. This can happen to enforce messaging policies or comply with regulations. Here’s how you can reduce the risk of your messages being filtered when using Stack.

Key Guidelines to Prevent Filtering​

To ensure your messages are delivered successfully, follow these best practices:

  • Obtain Consent: Only send messages to users who have explicitly opted in to receive them. Clearly identify yourself in the message and provide opt-out instructions.

  • Opt-Out Instructions: In the US and Canada, use "STOP" as the opt-out keyword (e.g., "Reply STOP to unsubscribe"). Avoid non-compliant phrases like "text 2 to opt out."

  • Regular Check-Ins: If you send messages over long periods, verify consent every 18 months. This helps ensure the recipient still wants your messages and that their phone number hasn’t changed owners.

  • Monitor Opt-Outs and Complaints: Keep an eye on opt-out rates and complaints. High rates may indicate issues with your consent process, leading to increased filtering.

Use Case and Sender Selection​

  • Review SMS Guidelines: Check the rules and best practices for each country you send messages to. This ensures compliance with local regulations.

  • Avoid Forbidden Categories: Ensure your use case isn’t among forbidden categories in the US and Canada.

  • Appropriate Sender IDs: Use the required sender IDs, like short codes or pre-registered Alphanumeric Sender IDs, for application-to-person (A2P) traffic. This can improve message delivery.

Message Contents​

  • Avoid URL Shorteners: Do not use shared public URL shorteners like TinyUrl or free Bitly links. Instead, use domains you control.

  • Use Clear URLs: If possible, use URLs specific to your business domain to reduce filtering risks.

  • Avoid Suspicious Content: Steer clear of emojis, excessive special characters, and poor grammar, as these can trigger filtering.

  • Comply with Legal Standards: Ensure your content is legal and not forbidden by carriers. Refer to forbidden message categories for more details.

Troubleshooting Mistaken Filtering​

If you suspect your messages are being mistakenly filtered:

  1. Gather Examples: Collect at least three examples of undelivered messages with error 30007 from the last seven days.

  2. Contact Support: Share these examples with our support team for further troubleshooting.

Sharing Undelivered Message Details​

To share details of undelivered messages:

  1. Go to the "Conversations" section in Stack.
  2. Search for the contact by name or email.
  3. Click on the contact image.
  4. Copy the link address at the top of the page.

For more insights on message filtering, refer to the article How Does Message Filtering Work?

By following these guidelines, you can significantly reduce the chances of your messages being filtered and ensure effective communication with your audience.