How to Fix “Error: Listen EADDRINUSE: Address Already in Use” in NodeJS

The “Error: listen EADDRINUSE” message is typically seen when trying to start a server on a port that is already in use by another application. To fix this error, you can try the following:

1. Find the process using the port: You can use the following command on your terminal (command prompt in Windows) to find the process using the port:lsof -i :<port-number>Replace <port-number> with the port number you are trying to use. This command will show you the process ID (PID) of the application using the port.
2. Stop the process using the port: Once you have the PID, you can use the following command to stop the process:kill <PID>Replace <PID> with the PID you obtained from the previous command. This will stop the application using the port.
3. Change the port number: If you cannot stop the application using the port, you can change the port number of your application to a different port that is not being used. You can update the port number in your code or configuration files and try starting the server again.
4. Wait for the port to become available: If you are sure that no other applications are using the port, you can wait for some time and try starting the server again. Sometimes it takes a few minutes for the port to become available after an application using the port has stopped.
5. “Address Already in Use” is a common error message that indicates that a network address, such as a port, is already being used by another application or process on the same machine.
6. This error usually occurs when you try to start a new application or service that requires a particular port number or network address that is already in use by another process or service. This can happen when you have multiple applications running on the same machine that are competing for the same resources.
7. To resolve this error, you need to identify which process is using the network address that your application needs and either terminate that process or configure your application to use a different network address. You can use tools like netstat or lsof to identify the process that is using the network address.
8. Alternatively, you can try restarting the machine or the process that is using the network address, which may release the address and allow your application to use it.

Once you have followed one of the above steps, try starting the server again on the desired port.