The reasons of a Hard Disk Clicking Sound

Head Crash This is a physical damage of the disk platter when the head of a hard disk scratches the surface of the disk. This is the result of the grinding sound you hear when this occurs. Firstly, turn off your computer and do not attempt to power it up. Prolong power to the hard disk will only cause it more harm and causing further complications. Consult a data recovery firm immediately and avoid dismantling the disk to repair the problem yourself. Operating without the correct tools and a lab environment can result in further extensive damage that complicates the data recovery process.
Bad Sectors Typically bad sectors are physical damage of a span of disk area. When the head make several attempts to read from the same area of disk multiple times but fails, it generates the clicking sound. This can also occur when the head is unable to calibrate with the media servo tracks due to the gradual weakening of the magnetic domains on the platter that causes the drive to reset continuously. Perform a disk surface scan if the condition of the hard disk is not too bad. This helps to mark all bad sectors and prevent your system from writing new data on the marked sectors of the disk.

Mechanical Faults This is a physical damage and these sounds can be caused by a malfunctioning spindle, Read Write head or loose components. Backup your data immediately if you are still able to access data on the disk. Your disk is near the end of its life and will stop functioning anytime. If your disk stops spinning after a period of clicking sound, you may wish to send your disk to a reputable data recovery firm to recover your data.

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