406
Not Acceptable
4xx Client ErrorWhat It Means
The server cannot produce a response matching the Accept headers sent by the client.
When You'll See It
Returned when content negotiation fails (e.g., client requests XML but server only supports JSON).
Related Status Codes
Frequently Asked Questions
What does HTTP 406 mean?
HTTP 406 Not Acceptable means: The server cannot produce a response matching the Accept headers sent by the client.
When does a server return 406?
Returned when content negotiation fails (e.g., client requests XML but server only supports JSON).
Is 406 a client error or server error?
HTTP 406 is a Client Error (4xx) response. This means the issue is on the client side — the request was incorrect or unauthorized.
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