We cannot change the application port from the avtivator but can change from the command line activator "~run 8080"
But to run on the poet 9000 from the activator we need to stop the application which is using this port. We can use the this application to find this and end the process https://technet.microsoft.com/en-in/sysinternals/bb897437.aspx
After this we can run and it will be successful.