# Troubleshooting CORS
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If you're experiencing issues with CORS, check the following:
+ **Verify CORS configuration** – Ensure your CORS configuration is properly formatted JSON and includes the necessary rules for your use case.
+ **Check origin matching** – The origin in your request must exactly match an entry in the `AllowedOrigins` list. Protocol (http/https), subdomain, and port must match exactly.
+ **Verify HTTP methods** – Ensure the HTTP method you're using is listed in the `AllowedMethods` for the matching rule.
+ **Check browser developer tools** – Use your browser's developer tools to inspect the preflight OPTIONS request and response to identify any CORS-related errors.
+ **Validate bucket permissions** – Ensure your bucket has the appropriate permissions configured in addition to CORS. CORS only controls browser-based cross-origin access, not bucket-level permissions.

If you need to remove the CORS configuration from your bucket while you troubleshoot, see [Remove CORS configurations](cors-configuration-cli.md#cors-remove-configuration).