Node.js Port 3000 already in use but it actually isn't?

Question

You can search on how to kill that process.

For Linux/Mac OS search (sudo) run this in the terminal:

$ lsof -i tcp:3000
$ kill -9 PID

On Windows:

netstat -ano | findstr :3000
tskill typeyourPIDhere 

change tskill for taskkill in git bash

Maybe you can take this as reference. This single command line can kill the process running on given port.

npx kill-port 3000

---

To kill multiple ports.

npx kill-port 3000 8080 4200

Sometimes it happens, as @sova proposed This happens to me sometimes, EADDR in use. Typically there is a terminal window hiding out in the background that is still running the app. And that's also right with me.

It happens, when you have opened terminal for long time, yeah you have right, you have stop the process. But sometimes it didn't stop in the background. So best solution is that you close the terminal and start it again. It will solves your problem. becuase in my case it works.

Also,

sudo lsof -i:<PORT_NO>

close the instance for present time but unable to stop the process in background. So for one time,

sudo kill <PID>

works, but again when we update our code and save, this problem occurs again as with Nodemon.

So exit the terminal will solve the problem. OR

  killall -9 node

I had the same problem. (The below steps work fine on Windows 10):

1. Open Task manager (press Ctrl+Alt+Delete)
2. Select the 'Processes tab'
3. Search for 'Node.js: Server-side JavaScript'
4. Select it and click on 'End task' button

Now you can run npm start.

Hope it helps you.