Error reason: You are trying to use the busy port number

Two possible solutions for Windows/Mac

1. Free currently used port number
2. Select another port number for your current program

Windows

1. netstat -ano | findstr :4200 2. taskkill /PID 5824 /F 

Mac

You can try netstat

netstat -vanp tcp | grep 3000 

For OSX El Capitan and newer (or if your netstat doesn't support -p), use lsof

sudo lsof -i tcp:3000 

if this does not resolve your problem, Mac users can refer to complete discussion about this issue Find (and kill) processes listening to port 3000 on Mac

Windows

set PORT=5000 

Mac

export PORT=5000 

Error reason: You are trying to use the busy port number

Two possible solutions for Windows/Mac

1. Free currently used port number
2. Select another port number for your current program

1. Free/Kill Busy Port Number

Windows

1. netstat -ano | findstr :4200 2. taskkill /PID 5824 /F 

Mac

You can try netstat

netstat -vanp tcp | grep 3000 

For OSX El Capitan and newer (or if your netstat doesn't support -p), use lsof

sudo lsof -i tcp:3000 

if this does not resolve your problem, Mac users can refer to complete discussion about this issue Find (and kill) processes listening to port 3000 on Mac

2. Change Port Number

Windows

set PORT=5000 

Mac

export PORT=5000 

Error reason: You are trying to use the busy port number

There are two possible solutions to resolve this issue on Windows/Mac

1. Free currently used port number
2. Select another port number for your current program

Windows

1. netstat -ano | findstr :4200 2. taskkill /PID 5824 /F 

Mac

You can try netstat

netstat -vanp tcp | grep 3000 

For OSX El Capitan and newer (or if your netstat doesn't support -p), use lsof

sudo lsof -i tcp:3000 

if this does not resolve your problem, Mac users can refer to complete discussion about this issue Find (and kill) processes listening to port 3000 on Mac

Windows

set PORT=5000 

Mac

export PORT=5000 

Error reason: You are trying to use the busy port number

Two possible solutions for Windows/Mac

1. Free currently used port number
2. Select another port number for your current program

Windows

1. netstat -ano | findstr :4200 2. taskkill /PID 5824 /F 

Mac

You can try netstat

netstat -vanp tcp | grep 3000 

For OSX El Capitan and newer (or if your netstat doesn't support -p), use lsof

sudo lsof -i tcp:3000 

if this does not resolve your problem, Mac users can refer to complete discussion about this issue Find (and kill) processes listening to port 3000 on Mac

Windows

set PORT=5000 

Mac

export PORT=5000 

Error reason: You are trying to use the busy port number

There are two options to resolve this issue in Windows/Mac

1. Free currently used port number
2. Select another port number for your current program

1. Free Port Number

Windows

1. netstat -ano | findstr :4200 2. taskkill /PID 5824 /F 

Mac

You can try netstat

netstat -vanp tcp | grep 3000 

For OSX El Capitan and newer (or if your netstat doesn't support -p), use lsof

sudo lsof -i tcp:3000 

if this does not resolve your problem, Mac users can refer to complete discussion about this issue Find (and kill) processes listening to port 3000 on Mac

2. Change Port Number?

Windows

set PORT=5000 

Mac

export PORT=5000 

Error reason: You are trying to use the busy port number

There are two possible solutions to resolve this issue on Windows/Mac

1. Free currently used port number
2. Select another port number for your current program

Windows

1. netstat -ano | findstr :4200 2. taskkill /PID 5824 /F 

Mac

You can try netstat

netstat -vanp tcp | grep 3000 

For OSX El Capitan and newer (or if your netstat doesn't support -p), use lsof

sudo lsof -i tcp:3000 

if this does not resolve your problem, Mac users can refer to complete discussion about this issue Find (and kill) processes listening to port 3000 on Mac

Windows

set PORT=5000 

Mac

export PORT=5000