ErrorFindly
4074xx Client ErrorHigh

HTTP 407 Proxy Authentication Required

Defined in RFC 7235

What Does HTTP 407 Mean?

The client must first authenticate itself with the proxy before the request can be processed.

Common Causes

  1. 1Corporate proxy requiring authentication
  2. 2VPN proxy credentials expired
  3. 3Proxy configuration missing credentials
  4. 4Intercepting proxy requiring login

Impact

  • ⚠Cannot access any websites through the proxy
  • ⚠All HTTP requests are blocked until proxy authentication is provided

Developer Fix

For web developers and application engineers

  1. 1Configure proxy credentials in HTTP client
  2. 2Handle 407 by prompting for proxy credentials
  3. 3Check Proxy-Authenticate header for auth method

Server Admin Fix

For system administrators and DevOps engineers

  1. 1Verify proxy authentication configuration
  2. 2Check LDAP/AD integration for proxy auth
  3. 3Review proxy access control lists

Frequently Asked Questions

How is 407 different from 401?
401 means you need to authenticate with the target server. 407 means you need to authenticate with an intermediary proxy. The proxy is blocking your request before it reaches the destination.
How do I fix a 407 error?
Provide your proxy credentials in your browser or application settings. If you're on a corporate network, contact your IT department for the correct proxy authentication details.

Related HTTP Status Codes

401Unauthorized403Forbidden

About the Author

Web Infrastructure Team

Verified against official RFC specifications and real-world server configurations. HTTP status code behavior confirmed across Apache, Nginx, and Cloudflare.