If i'm creating the RMI registry from command line, the client has no problem in binding objects to the registry. However, if i'm starting the RMI registry using ProcessBuilder, it's giving error. This is my code for creating rmiregistry using ProcessBuilder ProcessBuilder obj = new ProcessBuilder ("rmiregistry","2500"); Process obj_process = obj.start(); The error that i'm getting for using ProcessBuilder when I'm trying to bind to my own RMI registry java.rmi.ServerException: RemoteException occurred in server thread; nested exception is: java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is: java.lang.ClassNotFoundException: node_func node_func is an interface Any ideas?