A service provider places a server at a data center and a service user searches a website, connecting a terminal to the Internet. When the service user specifies a URL in a website server via a terminal accessable to the Internet, data of content stored onto the server is read out and transmitted to the terminal of the service user. The server stores customer information received from the service user and performs a customer registration as a merchandise purchaser. After completing a customer registration, information advising a membership registration different from a customer registration is transmitted to the service user.