A device and method are described to create a reply message in which, even in a case where electronic messages are exchanged among a plurality of users, a past electronic message to be referred to as a desired reply message can be efficiently retrieved, and trouble in creating a reply message can be reduced. When a first electronic message that has been stored most recently has been extracted from history information, and when an instruction indicating that the body part of the first electronic message is necessary has been accepted, the body part of the first electronic message is temporarily stored. A second electronic message that has been stored next most recently is extracted from the history information. When information on a source in the header part of the second electronic message does not match information on the author of a reply message, the address of the source is set to the address of the destination of the reply message, the temporarily stored body part is added to the reply message, and history information preceding the second electronic message is added.