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ERR_TUNNEL_CONNECTION_FAILED: How to Fix It

Your connection goes through a proxy, and the proxy couldn't open a tunnel to the website. The proxy setting is wrong, the proxy is down, or it blocks the site.

ERR_TUNNEL_CONNECTION_FAILED

Chrome asked a proxy server to connect it to the site, and the proxy said no or failed. Without that tunnel, HTTPS sites can't load.

Quick checks

  • Do you need a proxy (work network, school)? If not, turn proxies off.
  • Did a VPN or debugging tool recently quit? It may have left a proxy configured.

Fixes on Mac

  1. Turn off unwanted proxies

    1. System Settings › Network › Wi-Fi (or Ethernet) › Details › Proxies.
    2. Turn off Web proxy, Secure web proxy, SOCKS and Automatic proxy configuration unless you need them; click OK.

  2. Check for apps that set proxies

    1. Charles, Proxyman, VPN apps and some security tools set system proxies while running. Quit them cleanly or reset their proxy setting.
    2. Run scutil --proxy in Terminal to see the active proxy configuration.

Fixes on Windows

  1. Remove the proxy

    1. Settings › Network & internet › Proxy: turn off Use a proxy server and automatic setup scripts you don't use.

Other devices

  1. Phones

    1. Wi-Fi network settings › HTTP Proxy: set to Off.

Still not working?

ERR_PROXY_CONNECTION_FAILED is the related error when the proxy itself can't be reached. On a managed (work) Mac, proxy settings come from your organisation; contact IT rather than changing them.

See what’s happening

LightAtom's connections view shows all of Chrome's traffic going to a single proxy address when a proxy is in use.

Frequently asked questions

What does ERR_TUNNEL_CONNECTION_FAILED mean?

Chrome uses a proxy, and the proxy couldn't create the CONNECT tunnel needed for HTTPS to the site, because the proxy failed, blocked the site or isn't configured correctly.

How do I check proxy settings on a Mac?

System Settings › Network › your connection › Details › Proxies, or run scutil --proxy in Terminal to see what's active.

What is the difference from ERR_PROXY_CONNECTION_FAILED?

PROXY_CONNECTION_FAILED: Chrome can't reach the proxy at all. TUNNEL_CONNECTION_FAILED: it reached the proxy, but the proxy couldn't connect onward.

Related errors and tools

Related

LightAtom team

The people who build LightAtom, a network monitor for macOS.