Proxy Connection Errors

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Proxy connection errors occur when a client fails to establish or maintain a connection through a proxy server to its intended destination, typically due to network issues, misconfigurations, authentication failures, or server-side problems. These errors manifest in various forms, each indicating a specific underlying issue requiring targeted troubleshooting.

Common Proxy Connection Errors

1. Connection Refused / ECONNREFUSED

Cause: The proxy server actively rejected the connection attempt from the client. This generally means the proxy service is not running, is configured to listen on a different IP/port than the client expects, or an intervening firewall is blocking the connection to the proxy's listening port.

Solution:
* Verify Proxy Service Status: Confirm the proxy server process is operational on the host machine.
bash # For Linux systems using systemd (e.g., Squid) sudo systemctl status squid # For Windows, check services.msc for the proxy service
* Check Proxy Listening Configuration: Ensure the proxy server is bound to the correct IP address and port. Review the proxy's configuration file (e.g., squid.conf for Squid) for http_port or similar directives.
* Inspect Firewall Rules: Examine firewall configurations on the proxy server host, the client, and any intermediate network devices. Ensure rules allow TCP traffic to the proxy's listening port