Method for registering user information to exchange message on network

摘要

In a message exchange system, a first user and a second user mutually register their handle names (HNs) to their friend lists each provided in a server. When the first user deletes the registration of HN of the second user from the first user's friend list, the first user notifies the second user of the deletion of the HN via the server to request the second user to delete the registration of the first user's HN from the second user's friend list. The HN of the first user is deleted from the second user's friend list.