How to Fix Chrome Browser Proxy Error (ERR_PROXY_CONNECTION_FAILED) - Remote Desktop Gateway 404 Error: Missing Web Interface Fix-Command Prompt Server Timeout Troubleshooting

Updated 2026-06-14 12:47:25macos-help
How to Fix Chrome Browser Proxy Error (ERR_PROXY_CONNECTION_FAILED) - Remote Desktop Gateway 404 Error: Missing Web Interface Fix-Command Prompt Server Timeout Troubleshooting
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.