About the book: year / Laser disks are not very reliable storage media. Even if you handle them carefully, you are not immune from scratches and surface contamination (sometimes the disk mills the drive itself directly and you are powerless to resist this). But even a completely normal-looking disk may contain internal defects, leading to its complete or partial unreadability on standard drives. This is especially true for CD-R/CD-RW discs, the quality of which still leaves much to be desired, and the recording process is associated with the appearance of various types of errors. However, even in the presence of physical damage to the surface, a laser disc can be read quite normally due to the huge redundancy of stored data on it, but then, as defects grow, the corrective ability of Reed-Solomon codes suddenly ceases to be enough and the disk, for no apparent reason, refuses to be read, or is even not recognized by the drive at all. Fortunately, in the vast majority of cases, the information stored on the disk is all it is still possible to save and this article tells how.