Proxy Authentication and 407 Responses
Fix 407 Proxy Authentication Required — Basic auth, NTLM, IP allowlists, and credential debugging.
Fix 407 Proxy Authentication Required — Basic auth, NTLM, IP allowlists, and credential debugging.
Understanding 407
The proxy refused the request without valid credentials. Distinguish 407 from origin 401 responses.
Auth schemes
- Basic username:password
- NTLM in corporate proxies
- IP allowlisting without user auth
Related: auth best practices.
Debugging checklist
URL-encode special characters in passwords, verify allowlist IP, and confirm account quota with provider.
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