INFORMATION PROCESSING UNIT, INFORMATION PROCESSING METHOD, PROGRAM, AND INFORMATION PROCESSING SYSTEM

PROBLEM TO BE SOLVED: To provide an information processing unit, an information processing method, a program, and an information processing system, capable of preventing erroneous transmission of information by confirming the validity of the destination specified before transmission in an information transmission method such as mail and facsimile that sets the destination for transmitting the information.SOLUTION: An information processing unit, an information processing method, a program, and an information processing system include: management means for managing a valid period of destinations; acceptance means for accepting information to which the destination is specified; extraction means for extracting the destination specified in the information accepted by the acceptance means; determination means for determining whether an expired destination managed by the management means is contained in the destinations extracted by the extraction means; and suppressing means for suppressing the transmission of the information accepted by the acceptance means if an expired one is contained as a result of the determination made by the determination means.