Sender address setting when generating return mail

摘要

A standard mail address is assigned to each user who uses mail exchange service provided by a mail server. Each user can also have an extended mail address including a character name used in a network game provided by a game server. The extended mail address can be changed/deleted by user selection. When generating a return mail, a sender address of an original mail which is received from the mail server, is set to a destination address of the return mail. A destination address of the original mail is set to a sender address of the return mail when the destination address is currently available. When the destination address of the original mail is currently unavailable, the standard mail address is set to the sender address of the return mail.