|File system defragmentation is a tool for optimization, not a tool for repair. In fact, the extra strain on the disk during the defrag could cause the drive to fail faster.|
I don't know exactly which S.M.A.R.T. error you got, but best case scenario for you would be if the logic board is failing. If so, you could try to get a disk of the same make/model, and swap logic boards, but that's only easy if your drive is in the 3.5" form factor. If this is a laptop, and I'm assuming it is, you have a 2.5" drive. That means you may or may not require soldering equipment to remove the logic board.
So, how's that backup coming along?
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