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-When it was dropped, was it operating? Was it connected via USB to an OS like Windows with power cable plugged in? Or was it turned off and disconnected from both power and USB?
-how far was it dropped? Off a table…say 4 feet? The height is important. It is never good to drop a hard drive at any time but they are designed to handle moderate vibration. A drive might survive a short fall of a few inches, or if it is tipped over, but if it’s powered up and subjected to a sudden, hard vibration the heads may contact the surface or even get bent. Even if it’s not powered up and falls 4 feet that’s not good.
Also, a long fall may damage the bearings in the motors that power the platters and the head positioner. Damaged bearings could jam the motor enough to blow the drive circuitry on the circuit board.
-When you disassembled the unit, did you plug both the SATA connector and the SATA power into a known good ‘desktop’ computer? You did not say what you are using to power up the drive itself when it is removed from the MyBook case.
Please note: the newer MyBooks use hardware data encryption and you won’t be able to read data when plugged into a a desktop SATA connector. All you are trying to do is hear if the drive is ‘spinning up’. It sounds like a quiet whine that increases in frequency and if the heads operate you will hear a slight ‘clunk’ as the heads leave the parking area.
You need an independent SATA power source and SATA data connector. Be very careful when handling the drive that you don’t touch the printed circuit board on the drive or allow it to come into contact with metal while the power is on. Also, keep it away from material with static electricity.
You can use the metal chassis from MyBook and attach the drive to it using the three screws so the PCB is protected.
If you have the drive connected to independent SATA power/data connectors, have you listened in a quiet environment to it power up? If you have other drives powering up at the same time you turn on the desktop computer you need to have your ear close to the drive or use a stethoscope or a piece of rubber tubing, with one end at your ear and the other end touching the case of the drive.
A damaged drive may start to spin up then it starts to click repeatedly. That means it cannot read the data on the track it is trying to access. That could be bad heads, a bad head data amplifier or a bad PCB. It could also mean the disk surface is damaged.
If you get that far, so the drive spins right up then remains quiet, without spinning back down, that may be a good sign. It also might mean you have a damaged circuit board in your MyBook case or the power connector is broken, especially where it meets the circuit board.
If the drive does power up successfully in a desktop computer, and your drive has no encryptyion, you may be able to read it on your desktop.
Look at the circuit board in the MyBook case carefully with a magnifying glass. Look for apparent cracks in the circuit board, especially around areas where external connector connect to the circuit board.
If you are desperate and cannot afford data recovery there are sites on the Net for hard drives that may offer assistance. I have seen people replace heads, platters, and so on in a minimal environment but you cannot expect amazing results. It’s more often hit or miss.
If you have success getting your drive to read, it is highly advised to get the data off the drive immediately.