Last time I’ve experienced uncommon problem with one of my hard drives. Due a power failure of my NAS server a hard drive could’t spin up.
Disk tried to run several times and it finally started. Unfortunately BIOS of my NAS reported S.M.A.R.T. failure. One of the parameters was extremely low (‘failing now’ status). I suspected that disk was fine and I tried to recover “failing now” attribute to initial value.
CAUTION: Remember that all failed disks in production environment should be replaced for new ones. Described operation should be treated as experiment.
I found easy to use and free software that can modify S.M.A.R.T. attributes – Acronis Drive Monitor. I connected my SATA to USB converter and I installed mentioned software. Then I entered into S.M.A.R.T. options of my disk and I set “Spin Up Time” to high value (in this case 200). After several seconds new value was saved. I put disk into NAS. Now everything works good.