DUPLICATION PREVENTING METHOD FOR DIGITAL DATA FILE, AND RECORDING MEDIUM RECORDED WITH DUPLICATION PREVENTING PROGRAM

摘要

PROBLEM TO BE SOLVED: To prevent a digital data file from being unauthorizedly duplicated by permitting a limited uploading operation according to the given code value when an identification code that can confirm a purchasing destination is given to the digital data file and this file is uploaded into a personal computer terminal from a digital data player. SOLUTION: In this duplication preventing method, the identification code (header) of a digital data file to be uploaded is read. When it is decided that the uploaded data file is a file that was downloaded for pay, the uploading of the file is permitted only in the specific times. Thereafter, the identification code of the digital data file is changed to inhibit the file uploading operations more than the specific times.