What might indicate a bad sector on a hard drive?

Indications of a bad sector on a hard drive can manifest in various ways, but one of the most definitive signs is when the computer cannot read from the hard disk drive (HDD). A bad sector refers to a specific area on the disk that has become corrupted and is unable to store or retrieve data properly. When the read/write head of the drive encounters these defective areas, it will fail to access the data located there. This failure to read data is a direct result of physical or logical issues on the disk surface, prompting the hard drive to report errors that indicate the inability to complete read operations.

While the other scenarios might suggest problems with the hard drive or the system in general, they don't specifically confirm the existence of bad sectors. For instance, the computer recognizing the drive but being unable to access files could indicate file system errors or permission issues, rather than strictly bad sectors. Constant application crashes may stem from software issues or memory problems and not directly from the drive itself. Operating system corruption could be caused by various factors, including malware or improper updates, and may not necessarily point to physical problems with the HDD. Therefore, the inability to read from the HDD is a clear signal that could point to bad sectors and is an important diagnostic clue.