HTTP 406 Not Acceptable vs 451 Unavailable For Legal Reasons
Both HTTP 406 (Not Acceptable) and 451 (Unavailable For Legal Reasons) belong to the 4xx Client Error category. 406 indicates that the server cannot produce a response matching the Accept headers sent by the client. Meanwhile, 451 means that the server is denying access to the resource as a consequence of a legal demand. Named after Ray Bradbury's Fahrenheit 451.
Description
The server cannot produce a response matching the Accept headers sent by the client.
When You See It
When requesting a content type the server doesn't support (e.g., Accept: application/xml when only JSON is available).
How to Fix
Adjust the Accept header to a format the server supports.
Description
The server is denying access to the resource as a consequence of a legal demand. Named after Ray Bradbury's Fahrenheit 451.
When You See It
When content is blocked due to court orders, GDPR requests, or government censorship.
How to Fix
No technical fix. The block is legally mandated. Contact the site operator for details.
Key Differences
HTTP 406: The server cannot produce a response matching the Accept headers sent by the client.
HTTP 451: The server is denying access to the resource as a consequence of a legal demand. Named after Ray Bradbury's Fahrenheit 451.
You encounter 406 when when requesting a content type the server doesn't support (e.g., Accept: application/xml when only JSON is available).
You encounter 451 when when content is blocked due to court orders, GDPR requests, or government censorship.
When to Use Which
For 406 (Not Acceptable): Adjust the Accept header to a format the server supports. For 451 (Unavailable For Legal Reasons): No technical fix. The block is legally mandated. Contact the site operator for details.