Based on this old thread :
This error occurs when the REST call made by ADF to retrieve data from the specified URL fails because the resource is not found. Here are some steps you can take to troubleshoot the issue:
- Verify the URL: Double-check the URL you've configured in the ADF source settings for typos or incorrect formatting. Ensure the URL points to the exact location of the data you intend to retrieve from the REST API.
- Test the URL with a REST client: Use tools like Postman or curl to test the URL independently and see if it returns the expected data. This helps isolate if the issue lies with the URL itself or the way ADF interacts with it.
- Check authentication: If the REST API requires authentication, ensure the necessary credentials (e.g., access token) are provided correctly in the ADF linked service configuration.
- Firewall or Network Access: The error message also shows a “forbidden” error and an IP address. It’s possible that the IP address is being blocked by a firewall or doesn’t have network access to the URL.
- Examine API documentation: Refer to the documentation for the specific REST API you're using. The documentation might specify requirements or restrictions that could be causing the 404 error.
Hope this helps. Do let us know if you any further queries.