How to Fix Cloudflare 521 Error with Firewall Settings - How to Fix NET::ERR_CERT_AUTHORITY_INVALID from Chrome Policy-How to Fix Externally Managed Environment Error in Python venv

Updated 2026-07-28 16:20:46windows-fixes
How to Fix Cloudflare 521 Error with Firewall Settings - How to Fix NET::ERR_CERT_AUTHORITY_INVALID from Chrome Policy-How to Fix Externally Managed Environment Error in Python venv
Before changing system settings, save your work and note the exact error text so you can compare results after each step.

Extra verification checklist

  • Restart the affected app after changing permissions or configuration files.
  • Test the same workflow in a clean browser profile or a temporary user account.
  • Compare the result on another network if the error may be connection related.