← All Status Codes
406
Not Acceptable
⚠️ Client Error
Low Risk
📖 What Is HTTP 406?
The server cannot produce a response matching the Accept headers sent by the client. Content negotiation failed.
🛡️ Security Implications
Low risk. Can indicate API misuse. Ensure error responses do not leak internal details about available content types.
🔍 Common Causes
Client requests a content type the server cannot produce (e.g., Accept: application/xml when only JSON is available).
🔧 How to Fix
Adjust the Accept header to match available content types. Check API documentation for supported response formats.
🖥️ How to Check
curl -I -o /dev/null -w "%{http_code}" https://example.com