To speedily investigate the cause of a reported fault and to realize clear measures against it by considerably suppressing the deterioration of performance by means of the operation of a logging means and enlarging the acquirement object of fault information as much as possible especially in the tracking of the fault whose generation frequency is low.

A data acquirement means 102 acquires condition data and a condition judgement means 103 judges whether acquired condition data satisfies the specified starting condition where a probability that the fault occurs is high. The logging means 104 is operated only when the condition is satisfied and operation history information is registered in a product. In a regular processing which does not satisfy the condition, operation history information is not registered in the product and it is shipped.