permision denied on port 3000 on nodejs - node.js

Question

when i run my nodejs project on port 3000, get following error:
Error: listen EACCES: permission denied :::3000
at Server.setupListenHandle [as _listen2] (node:net:1330:16)
at listenInCluster (node:net:1378:12)
at Server.listen (node:net:1465:7)
at Function.listen (F:\Projects\NodeJS\Nodejs start\Nodejs start\node_modules\express\lib\application.js:618:24)
at Object.<anonymous> (F:\Projects\NodeJS\Nodejs start\Nodejs start\app.js:34:5)
at Module._compile (node:internal/modules/cjs/loader:1103:14)
at Object.Module._extensions..js (node:internal/modules/cjs/loader:1155:10)
at Module.load (node:internal/modules/cjs/loader:981:32)
at Function.Module._load (node:internal/modules/cjs/loader:822:12)
at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:77:12)
Emitted 'error' event on Server instance at:
at emitErrorNT (node:net:1357:8)
at processTicksAndRejections (node:internal/process/task_queues:83:21) {
code: 'EACCES',
errno: -4092,
syscall: 'listen',
address: '::',
port: 3000
Not only on port 3000, but also on any port, the program does not run, and the mentioned error occur.
for solving this problem, i run net stop winnat on CMD, i get:
The Windows NAT Driver service is not started.
for start the winnat, i run net start winnat , i get
The Windows NAT Driver service was start successfully.
But the problem was not solved.Is there any other way but to restart the system?

Answer 1

When reading an environment variable, you should convert it to a number.
Try adding parseInt() to the variable:
const port = parseInt(process.env.PORT) || 3000;

Answer 2

You can try On Windows systems, restarting the service "Host Network
Service" may resolve the issue.
or try to restart your computer more than one time
or try open CMD under admin rights and run :
net stop winnat
net start winnat