Troubleshooting Port conflict in Websphere Portal

Today, I found this strange error while starting "Websphere application server" and "Websphere Poral server" on my box which already running one more instance of WPS. I was able to start only one process at a time but not both. I got this error while starting the server1 when websphere Portal is already started.

WsServerImpl E WSVR0009E: Error occurred during startup
com.ibm.ws.exception.RuntimeError: com.ibm.ws.exception.RuntimeError: org.omg.CORBA.INTERNAL: CREATE_LISTENER_FAILED_4 vmcid: 0x49421000 minor code: 56 completed: No

This was due to port conflict between processes "server1" and "Websphere Portal". To resolve this perform the following steps.

1. Stop all WebSphere processes: Application Servers, nodeagents, and the deployment manager.
2. View all ports in use on the operating system by issuing a netstat -a command. Make note of any ports in use.
3. Open the serverindex.xml file for your server. You can find it in the directory /config/cells//nodes//serverindex.xml
4. Check this file for any of the port conflict with the result in step-2.
5. Resolve the port conflict by editing the serverindex.xml and change the conflicting port number to one that is not in use, then restart all the WebSphere processes.