Quick Summary
The "ERR_TUNNEL_CONNECTION_FAILED" error in Chrome indicates that your browser is unable to establish a connection through the proxy server you're using to reach the website. This often points to issues with the proxy server itself, your network configuration, or firewall settings.
Common Causes
- Proxy Server Issues: The proxy server you are configured to use might be down, overloaded, or experiencing technical difficulties. A faulty proxy can prevent your browser from properly establishing a connection to the internet.
- Incorrect Proxy Configuration: Your browser or system might be configured to use a proxy server that is no longer valid or configured incorrectly. This could be due to a typo in the proxy settings or an outdated configuration.
- Firewall Interference: A firewall on your computer or network might be blocking the connection to the proxy server. This is especially common in corporate networks with strict security policies.
- Network Connectivity Problems: General network connectivity issues, such as a problem with your internet service provider (ISP) or a faulty router, can prevent your browser from reaching the proxy server.
- Antivirus Software Interference: Some antivirus software can interfere with network connections, including proxy connections. Its real-time scanning or web protection features might be misinterpreting the proxy connection as a threat.
Step-by-Step Fixes
Method 1: Check Proxy Settings in Chrome
Step 1: Open Chrome's settings by typing chrome://settings in the address bar.
Step 2: Search for "proxy" in the settings search bar.
Step 3: Click on "Open your computer's proxy settings".
Step 4: Depending on your system, you'll see options to configure proxy settings.
Step 5: If you're not supposed to be using a proxy, ensure that the "Use a proxy server" option is disabled (or set to 'Automatically Detect Settings').
Step 6: If you are supposed to be using a proxy, double-check the proxy address and port number for accuracy. Contact your network administrator if you are unsure of the correct settings.
Method 2: Disable Proxy (If Not Required)
Step 1: Open Chrome's settings (chrome://settings).
Step 2: Search for 'proxy' and open computer's proxy settings.
Step 3: Find the Proxy settings, and disable "Use a proxy server for your LAN" (or similar wording depending on OS). Ensure 'Automatically detect settings' is enabled.
Step 4: Restart Chrome to apply the changes.
Method 3: Check Firewall Settings
Step 1: Open your operating system's firewall settings (search for "Firewall" in your system's search bar).
Step 2: Ensure that Chrome (or the proxy server, if applicable) is allowed to communicate through the firewall.
Step 3: You may need to add Chrome as an exception if it's being blocked.
Step 4: Temporarily disable the firewall to see if that resolves the issue. If it does, you'll need to configure the firewall to allow Chrome and/or your proxy server to function correctly.
Method 4: Restart Your Router and Modem
Step 1: Unplug your modem and router from the power outlet.
Step 2: Wait for about 30 seconds.
Step 3: Plug the modem back in and wait for it to fully power on.
Step 4: Plug the router back in and wait for it to fully power on.
Step 5: Try accessing the website again.
Method 5: Disable Antivirus Temporarily
Step 1: Temporarily disable your antivirus software.
Step 2: Try accessing the website again.
Step 3: If the issue is resolved, configure your antivirus software to allow Chrome and/or your proxy server to access the internet without interference. Consult your antivirus software's documentation for instructions on how to create exceptions.
Step 4: Remember to re-enable your antivirus software after testing.