To install program data without enciphering them, to activate sample software on the set date and time and to confirm all functions by incorporating trial limit data for permitting the install of application program(AP) data and the activation of that program within the date and time preset to the sample software.

Concerning a storage medium 12, the computer of a central control part 8 reads the sample software, in which the trial limit data for limiting the trial of AP data and that program corresponding to the date and time through a reading part 13. On the current date and time counted by a time count part 7, a judging part 8a judges whether these data can be tried or not. When the trial is disabled, it is reported by a reporting part 2-1 but when the trial is enabled, an activating part 8b installs the AP data in a previously provided program data buffer 11-2 and activates the AP.