WSAEADDRINUSE 0x80072740
Error code 10048 · HRESULT 0x80072740
Only one usage of each socket address is normally permitted.
Also searched as: 10048, error 10048, socket error 10048, address already in use, only one usage of each socket address is normally permitted
What it means
Winsock error 10048 "Address already in use" appears when a program tries to listen on a port that another process already uses. Developers see it when starting web servers, databases or game servers, often after a previous instance did not exit. Only one process at a time can normally bind a given IP and port.
Applies to: Windows 10, Windows 11
How to fix WSAEADDRINUSE
- Find the process using the port: netstat -ano | findstr :PORT, then look up the PID in Task Manager > Details
- Stop the old instance or end that PID with taskkill /PID number /F
- Change your application to use a different free port
- Check reserved ranges with netsh interface ipv4 show excludedportrange protocol=tcp; Hyper-V, WSL and Docker can reserve blocks of ports
- Wait a minute and retry if the previous instance just closed and the port is in TIME_WAIT
- Restart the computer if the port stays held by a stuck process
Why it happens
Another process (often a second copy of the same app) holds the port, the port sits in a range reserved by Windows networking features, or a socket from a crashed process is still closing.
FAQ
Why is a port in use when nothing is running?
Windows may have reserved it for Hyper-V, WSL or Docker; check excludedportrange with netsh.
Is 10048 the same as EADDRINUSE?
Yes, it is the Windows Sockets equivalent.
Related errors
Source: Microsoft WinError.h · fixes written and reviewed by the editors (see our editorial policy)
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