Abstract: In a method for managing product information, warranty information corresponding to a purchased product identification received from a customer-terminal used by a customer is retrieved from a sales information management database, managing the purchased product identification identifying a product that the customer purchased and warranty information showing a warranty of the product, and then conducting a request process corresponding to a request item indicated from the customer-terminal.

Abstract: The present invention provides a control information management method, a control object controlling method, a recording medium, a control information management server, and a control information management system, by any one of which registered information can be collectively managed and altered in accordance with alteration information, and a control object can be controlled in accordance with control information. The control information management system of the present invention includes a control information management server and a household appliance control device. The control information management server produces control information for controlling control objects in compliance with an instruction from a user, collects alteration information for altering the control information, alters the control information in accordance with the alteration information, and transmits the control information via a communication network.

Abstract: In a method for managing product information, warranty information corresponding to a purchased product identification received from a customer-terminal used by a customer is retrieved from a sales information management database managing the purchased product identification identifying a product that the customer purchased and the warranty information showing a warranty of the product and then a request process corresponding to a request item indicated from the customer-terminal is conducted.

Abstract: An access contract changing method can easily change an access contract between a prepaid contract and a postpaid contract so as to reduce inconvenience to a portable phone user. A server (50) of a communication service provider has a client information management system (58) for managing access service to the client. The server (50) changes the access contract between the prepaid contract and the postpaid contract by sending an instruction regarding the access contract to the client information management system in response to a predetermined action made by the client.