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charles-proxy

"ERR_TUNNEL_CONNECTION_FAILED" when using Charles Proxy

I have installed Charles Proxy in windows 10, and I have did the following settings:

  • installing ssl certificate
  • enabling ssl proxy
  • put "*" in the host and "443" in the port
  • The Firewall, antivirus, and VPN are all disabled

Most sites are reachable like google, facebook, reddit. But some sites aren't reachable and show as image link below: This site can't be reached.

And in Charles Proxy, the error is SSL handshake as image link below: ssl: received fatal alert: internal_error

Exhausted available SSL/TLS protocols, trying with everything enabled

This problem is occurred in all browser. But when using Fiddler proxy, all sites are reachable.

I have tried everything. What should I do?

Solution

  • From the screen shot one can see that you are using a pretty old version of Charles proxy 3.12.3 and most likely you are also using a pretty old version of Java to run Charles proxy.

    The server www.carnival.com Charles fails to connect to supports only TLS 1.2 and TLS 1.3 and the list of ciphers is restricted, too.

    If you are e.g. using an outdated Java version it is reasonable that the required TLS version is not supported and/or none of the required ciphers is supported by the used Java version.

    Conclusion: Al least upgrade to a newer Java version, e.g. the latest Java 8 runtime. This version supported all modern TLS versions and ciphers.