that the drive is failing and whilst you can I would copy all the contents off before it fails entirely.
What can be done? I'm no expert but I doubt it is economical to have it repaired. Drives do fail and when they do we just replace them.
You say you tested the electronics but a better test may be to attach the hdd to some other enclosure and see if it spins up properly and if the system can read it.
I hope this wasn't your only copy of your data.
Mark
I built my own portable HDD using a USB-sATA enclosure and a sATA 2.5 inch HDD. It works very well for almost 2 yrs but it recently stop to work. I just checked that the electronics on the case is OK but the HDD doesn't spin in the way that it use to do. When it works fine it had a continous noise like a jet... now it has an intermitent noise. It seems that it try to accelerate but it can't, then the computer doesn't recognize the disk. Is there similar experiences, and most important: How to repair it, at least one time to recover the data?

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