Test whether a website or server port is reachable — via Microsoft Learn

Commandlow riskWindows 11Windows 10

Instead of guessing whether a firewall is blocking something, PowerShell's Test-NetConnection tries a real TCP connection to any host and port and tells you TcpTestSucceeded True or False.

Takes effect right away

Command

Run in a normal PowerShell / Terminal window.

Test-NetConnection -ComputerName example.com -Port 443
Test-NetConnection -ComputerName 192.168.1.10 -Port 3389 -InformationLevel Detailed

Undo

# Read-only test: nothing to undo.

Detailed output adds the interface and source address used, which helps with VPN or multi-adapter problems. Without -Port it does a ping test.

Sources

Test-NetConnection — by Microsoft Learn

Source reviewed: 2026-11-02
Link checked: 2026-11-02
Tested hands-on: Not by Oddbyte.Me

Oddbyte.Me hasn't tried this on every Windows build, so keep the undo handy.

test-netconnectionport checkfirewallpowershelltelnet alternative

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