Getting HTTP 407 Proxy Authentication Required – How to Fix It? or Why Am I Seeing HTTP 407 and How D

http 407 usually means the proxy’s being stubborn.

Try this:
1. Clear *just* the proxy auth cache (not regular cache).
2. Reboot (annoying, but works sometimes).
3. If all else fails, use `curl -v` or Postman to test the proxy outside the browser. Might reveal the real issue.