Controlling an information recording apparatus for recording information in a detachable, re-writable storage medium which has a storage size exceeding a maximum allowable size of a first file system. When externally input information is stored in a single storage medium having a first storage area initialized by the first file system, and a second storage area initialized by a second file system which can access an area that exceeds the maximum allowable size of the first file system, the externally input information is stored in the second area, and information derived from the externally input information is stored in the first area. Link information between the information stored in the second area and the derivative information stored in the first area is recorded in the second area as management information.