Node throw er; after npm start

[Ahrovan]

Always show
node:events:496
throw er; // Unhandled 'error' event
^
after run npm start.

System:

• JHipster release v8.4.0
• java --version
  openjdk 21.0.3 2024-04-16 LTS
  OpenJDK Runtime Environment Temurin-21.0.3+9 (build 21.0.3+9-LTS)
  OpenJDK 64-Bit Server VM Temurin-21.0.3+9 (build 21.0.3+9-LTS, mixed mode, sharing)
• node --version
  v20.12.2
• Windows 11

1. First run ./mvnw and result:

---

    Application 'App' is running! Access URLs:
    Local:          http://localhost:8080/
    External:       http://xxx.xxx.xxx.xxx:8080/
    Profile(s):     [dev, api-docs]

---

2. then run npm start and result:

Compiled successfully.
[ Browsersync ] Proxying: http://localhost:4200
[ Browsersync ] Access URLs:

   Local: http://localhost:9000
External: http://xxx.xxx.xxx.xxx:9000

---

      UI: http://localhost:3001

UI External: http://xxx.xxx.xxx.xxx:3001

node:events:496
throw er; // Unhandled 'error' event
^

Error: listen EACCES: permission denied 0.0.0.0:3001
at Server.setupListenHandle [as _listen2] (node:net:1880:21)
at listenInCluster (node:net:1945:12)
at Server.listen (node:net:2037:7)
at Object.startServer [as fn] (...\node_modules\browser-sync-ui\lib\async.js:123:39)
at ...\node_modules\browser-sync-ui\lib\UI.js:185:14
at iterate (...\node_modules\async-each-series\index.js:8:5)
at ...\node_modules\async-each-series\index.js:16:16
at ...\node_modules\browser-sync-ui\lib\UI.js:193:13
at Object.setUrlOptions [as fn] (...\node_modules\browser-sync-ui\lib\async.js:76:9)
at ...\node_modules\browser-sync-ui\lib\UI.js:185:14
at iterate (...\node_modules\async-each-series\index.js:8:5)
at ...\node_modules\async-each-series\index.js:16:16
at ...\node_modules\browser-sync-ui\lib\UI.js:193:13
at Object.setBsOptions [as fn] (...\node_modules\browser-sync-ui\lib\async.js:48:9)
at ...\node_modules\browser-sync-ui\lib\UI.js:185:14
at iterate (...\node_modules\async-each-series\index.js:8:5)
at ...\node_modules\async-each-series\index.js:16:16
at ...\node_modules\browser-sync-ui\lib\UI.js:193:13
at ...\node_modules\browser-sync-ui\lib\async.js:20:13
at ...\node_modules\portscanner\lib\portscanner.js:230:7
at ...\node_modules\portscanner\node_modules\async\dist\async.js:972:16
at next (...\node_modules\portscanner\node_modules\async\dist\async.js:5228:18)
at ...\node_modules\portscanner\lib\portscanner.js:216:9
at Socket. (...\node_modules\portscanner\lib\portscanner.js:132:5)
at Socket.emit (node:events:518:28)
at TCP. (node:net:337:12)
Emitted 'error' event on Server instance at:
at emitErrorNT (node:net:1924:8)
at process.processTicksAndRejections (node:internal/process/task_queues:82:21) {
code: 'EACCES',
errno: -4092,
syscall: 'listen',
address: '0.0.0.0',
port: 3001
}

Node.js v20.12.2

[mraible]

The error message seems to indicate you already have something running in port 3001 or you don't have permission to run anything on that port.

[Ahrovan]

@mraible
here https://www.jhipster.tech/using-angular/

**4.**Now run ./mvnw or ./gradlew to launch the application server and it should be available at localhost:8080 this also serves the client side code compiled from the above steps.
5. Now run npm start in a new terminal to launch Webpack dev-server with BrowserSync. This will take care of compiling your TypeScript code, and automatically reloading your browser.

but in step 5, always i see error. now can not automatically reloading browser for Development.

[Ahrovan]

solved
net stop winnat
net start winnat