When using the WhatsApp Business API, you may encounter Error Code 0 (AuthException) with a 401 Unauthorized status. This error indicates an authentication problem, usually caused by issues with the access token.

What is AuthException (Error Code 0)?

AuthException (Error Code 0) signals that your app couldn't authenticate the user, commonly due to:

  • Access token expired.

  • Access token invalidated.

  • The user changed settings to restrict app access.

Solutions for Error Code 0

Here’s how to resolve AuthException:

  1. Generate a new access token to replace the expired or invalidated one, and update it in your system (steps explained further).

  2. Confirm that the user has granted your app the required permissions. If access is restricted, request them to re-enable permissions.

To Generate a New System User Access Token:

  1. Log into Meta Business Suite.

  2. Choose your business account from the top-left dropdown, then click the Settings (gear) icon.

  3. Go to Business settings.

  4. Click User > System users.

  5. Find and select the system user you need from the list.

  6. Click Generate new token.

  7. Choose the app that will use the token.

  8. Select the necessary Graph API permissions for the app, then generate the token.

For further troubleshooting tips on WhatsApp API errors or insights into maximizing the potential of WhatsApp Business API, visit heltar.com/blogs.