feel a very slight vibration. If it isn't spinning, there is a possibility that it simply isn't getting power to the motor. If that's the case, you may be able to disassemble the device and either connect the drive directly to a port in the PC or put it into another external case. If no luck, there are professional data recovery services but you'd be looking at several hundred dollars for retrieval.
My sister has an external 500 GB from Western Digital (MyBook I think it is), and as the title says it has stopped spinning. She can still plug it in and the light turns on, but she can't hear it spinning anymore and the computer doesn't see it.
Prior to it failing completely she told me it would sporadically fail on occasion, and she would unplug it and replug it and it would work again for a while. Now it won't work at all.
She would like to, first of all, know if it's at all possible to recover that data she had on it. If so, how much will it cost to get it done? And finally, who might be able to get it done. She was thinking of asking GeekSquad.
She has a lot of pictures on there, family and friends and trips and stuff, if we could save it it would be really appreciated.

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