BuyProxies: Windows PowerShell 5.1 empty native argument reproduction
Reviewed and tested October 12, 2026.

Requirements: Windows, Python 3.10 or newer, Windows PowerShell 5.1, and curl.exe.
Read reproduce.py before running. No additional Python packages are needed.

Run from the extracted folder:
  python -B reproduce.py

The script binds an ephemeral port on 127.0.0.1. Both the HTTP proxy and
destination are this local fixture. It uses synthetic credentials, clears
proxy environment variables only in child processes, sets a deliberate
loopback bypass, and never forwards, resolves external names or contacts a
proxy provider. It does not change Windows settings or require admin rights.

Expected result on the tested PowerShell 5.1.26100.9549 / curl 8.21.0:
  Original --noproxy '': IP/password cases each return exit 0, but two
  requests and zero correctly routed proxy requests.
  Corrected quoted empty value: each case records one correctly routed
  request; synthetic password authentication is checked after decoding.
  The reproduction exits 0 only if all four expected controls are observed.

reproduction-result.json is created beside the script. It contains versions,
counts and results; no real credentials or user IPs are collected. The script
closes its server on completion. Other curl versions may produce different
controls; retain the resulting report instead of assuming success.

This test is HTTP loopback only. It does not qualify HTTPS CONNECT, TLS,
SOCKS5, provider speed/availability or PowerShell 7 behavior.
Article: https://buyproxies.org/powershell-proxy-guide#bp-powershell-curl-empty-argument
