PREPAID CARD SYSTEM, CARD READER AND CARD UNAUTHORIZED USE PREVENTING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a prepaid card system which can prevent the unauthorized use of a prepaid card and to provide a card unauthorized use preventing method. SOLUTION: This reader 2 receives a prepaid card, reads stored information containing amount information stored in the prepaid card and updates/returns amount information corresponding to a use amount. The reader 2 checks the presence or the absence of the contradiction in stored information which is read from the prepaid card. When contradiction exists, the card is considered to be used in unauthorized manner the prepaid card and is taken in without returning it. Contradiction information containing a contradiction content is recorded, and a control program is deleted and the operation of the reader 2 is disabled.