This situation is called "disc selection" or "disc selection". Reasons for selecting a disc for an optical drive or DVD player: If the optical drive is difficult to read or not to read, it is necessary to doubt whether the optical head is dirty after eliminating the problem factors of the optical disc. If it is used frequently before, the optical head will age, the laser power will drop, and it may be difficult to read the disc or not to read the disc. If it is dirty, you can clean it with a VCD cleaning disk (if you have the ability, you can also open it and wipe it with a cotton swab dipped in head cleaner). If not, it is estimated that the bald head is aging. Although it is not used much, it may deteriorate prematurely due to factors such as quality or environment. But I think it is more likely to be dirty. The easiest way to judge whether there is a problem with the food is to take it to a friend's CD-ROM drive. If more than three optical drives can't read or it is difficult to read, it can be judged that the quality of the disc is poor, damaged or data is lost.