kubectl unable to connect to server: x509: certificate signed by unknown authority

One more solution in case it helps anyone:

My scenario:

• using Windows 10
• Kubernetes installed via Docker Desktop ui 2.1.0.1
• the installer created config file at ~/.kube/config
• the value in ~/.kube/config for server is https://kubernetes.docker.internal:6443
• using proxy

Issue: kubectl commands to this endpoint were going through the proxy, I figured it out after running kubectl --insecure-skip-tls-verify cluster-info dump which displayed the proxy html error page.

Fix: just making sure that this URL doesn’t go through the proxy, in my case in bash I used export no_proxy=$no_proxy,*.docker.internal