HTTP status codes / 4xx — Client error

451 Unavailable For Legal Reasons

What it means

The server refuses to serve the content because a legal demand — court order, sanctions, DMCA, GDPR block — prohibits it. Numbered after Bradbury's Fahrenheit 451.

What causes it

Geo-blocking for legal compliance, takedown orders, region-restricted content.

How to fix it

Nothing technical to fix; the block is jurisdictional. The response should say which legal demand applies.