4×× - Client Error

407 Proxy Authentication Required

Similar to 401 Unauthorized, but it indicates that the client needs to authenticate itself in order to use a proxy.

The proxy MUST send a Proxy-Authenticate header field¹ containing a challenge applicable to that proxy for the target resource. The client MAY repeat the request with a new or replaced Proxy-Authorization header field².

---

• ¹ Proxy-Authenticate RFC7235 Section 4.3
• ² Proxy-Authorization RFC7235 Section 4.4
• Source: RFC7235 Section 3.2

407 Code References

• Rails HTTP Status Symbol: :proxy_authentication_required
• Go HTTP Status Constant: http.StatusProxyAuthRequired
• Symfony HTTP Status Constant: Response::HTTP_PROXY_AUTHENTICATION_REQUIRED
• Python2 HTTP Status Constant: httplib.PROXY_AUTHENTICATION_REQUIRED
• Python3+ HTTP Status Constant: http.client.PROXY_AUTHENTICATION_REQUIRED
• Python3.5+ HTTP Status Constant: http.HTTPStatus.PROXY_AUTHENTICATION_REQUIRED