When the power goes out, there are a lot of questions that come to mind. What happened to cause the outage? When will the power come back on? Lower on the list of concerns may be whether or not your computer shut down properly when it lost power.
In this case, the user’s desktop computer did not shut down properly. Oftentimes, this does not create problems for the computer’s equipment, but in this case it caused the hard drive to fail. When the computer was turned back on, the drive began to make a clicking noise and platters were not spinning.
When a hard drive runs normally, the spinning platters generate enough “wind” to keep the read/write heads floating above their surface. During a normal shutdown, the platters spin to a stop slowly, and the heads repark to their original position without touching the surface of the platters.
However, in this case, the power outage caused an improper shutdown, and the read/write heads did not repark correctly. Instead of floating over the surface of the platters, they dragged across them, resulting in damage to the heads. Engineers determined they would need to be replaced in order to recover the data.