Which process is using a port?

Short answer Map listening sockets to process IDs and process names.

When to use it

For port conflicts, unexpected listeners or a service that cannot bind.

Map listeners

Get-NetTCPConnection -State Listen | Select-Object LocalAddress,LocalPort,OwningProcess,@{N="Process";E={(Get-Process -Id $_.OwningProcess -ErrorAction SilentlyContinue).ProcessName}}

Note

Run elevated for complete results.

Specific port

Get-NetTCPConnection -LocalPort 443 | ForEach-Object {Get-Process -Id $_.OwningProcess}

Note

Replace the port.

Caution

Do not kill a process before checking dependencies and business impact.