FAQ

FAQ

A port is in use, but portcheck shows no process. The process belongs to another user. Run with sudo (macOS, Linux) or as Administrator (Windows). Permissions by OS

A container's port shows docker-proxy or com.docker.backend. portcheck couldn't reach the container engine. Check that docker ps works for your user, or set DOCKER_HOST. Containers & WSL

Windows says a port is denied, but nothing uses it. Hyper-V, WSL2 or Docker has reserved it. See the reserved ranges with netsh interface ipv4 show excludedportrange protocol=tcp, and pick a port outside them.

kill says "refusing to kill protected process". That's on purpose: portcheck never stops system processes, itself, or its parent. Safety

How is this different from lsof, netstat or ss? It's the same commands, output, JSON and exit codes on every OS, plus "is this port really free?", "find me a free port" and a safe kill.

Does portcheck send telemetry? No. It makes no network connections except the ones scan makes to the targets you give it. Privacy

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