PURPOSE: To inspect the system usage right of a user so as to execute the continuous use of a system even if a fault occurs in an individual attribute table by analizing request information and referring to individual information from the individual attribute table or an alternate table.

CONSTITUTION: When there is a sub-system for inspecting the usage right of the user, user attribute information is requested to a request information analizing means 1. The request information analizing means 1 analizes which information is needed and transfers the control of reference to an information referring means 2 when information should be referred. The information referring means 2 referrs to information which should be referred from the individual attribute table 4 stored in a file and referrs to information from the alternate table 5 stored in main storage when the fault exists in the individual attribute table 4. An information returning means 3 returns information which is referred in the information referring means 2 to a request source which requests the reference of information.