Running on your computer
“Port 3000 is already in use”
- What you see
- Starting the app fails with
EADDRINUSEor says port 3000 is in use. - Why it happens
- Another copy of the app (or another app) is already running on that port.
- How to fix it
- Look for another terminal running
npm run devand stop it (Ctrl + C). - Or ask your agent to find and stop the process using port 3000.
- Look for another terminal running
Message for your agent
My app says port 3000 is already in use. Find what's using it, tell me what it is, and stop it if it's an old copy of my app.
Tip
How to prevent it: Stop the app when you finish a session.
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