Abstract: First error-processing data are generated with respect to a predetermined amount of data, and second error-processing data are generated with respect to each of a plurality of blocks produced by dividing the predetermined amount of data. Data of record units are generated from the predetermined amount of data, the first error-processing data, and the second error-processing data. The data of record units are recorded on and reproduced from a recording medium. Errors are corrected in the predetermined amount of data in the reproduced data of record units with the first error-processing data with respect to each of the record units. If errors cannot be corrected, at least errors are detected in the predetermined amount of data in each of the blocks with the second error-processing data.