A data processing system and method are disclosed for permitting only preregistered client computer hardware to access a service executing on a remote server computer system. A log-in token is established including a unique identifier which identifies a particular client computer hardware. The client computer hardware logs-on to the server computer system. Subsequent to the client computer hardware logging-on to the server computer system, the client computer hardware attempts to access the service. During the attempt, the client computer hardware transmits the log-in token to the server computer system. The server computer system utilizes the unique identifier included within the log-in token to determine if the client computer hardware is registered to access the service. In response to a determination that the client computer hardware is registered to access the service, the server computer system permits the client computer hardware to access the service. In response to a determination that the client computer hardware is not registered to access the service, the server computer system prohibits the client computer hardware from accessing the service.