When it comes to computer repair, hard drive failures are among the top issues I deal with. A failed hard drive can be disastrous. But with some regular maintenance, you can keep your hard drive spinning like a top. Here's how to keep your hard drive healthy.

Hard drive failures fall into two (2) classes: Predictable and Unpredictable. Predictable failures arise from mechanical wear and the eventual degrading of the storage surface. Unpredictable failures come from parts becoming defective or sudden mechanical failures. Around 60% of hard drive failures are from gradual wear and tear from daily use. With regular maintenance, you may be able to find, fix, and repair problems before they become catastrophic.
CHKDSK (check disk)

CHKDSK running on Windows 10 Tech Preview boot
Every operating system has a built-in utility for checking the health of your hard drive. In the early years of Windows (when it ran on top of DOS), there was ScanDisk. When Microsoft came out with Windows NT and NTFS, the disk checking utility changed to CHKDSK and is still in use today. The functionally has been expanded, but the commands have changed very little. CHKDSK verifies the integrity of the file system and fixes logical file system errors. It can also check for bad sectors and mark them as bad, but it cannot repair them. Cost: Free
Run CHKDSK in Windows XP
Run CHKDSK in Windows Vista / Windows 7
Run CHKDSK in Windows 8.1
Run CHKDSK in Windows 10
Manufacturer's software

UBCD HDD diagnostics list A thru P
Almost all hard drive manufacturers have utilities to check their drives for errors. Their software can check the SMART (Self-Monitoring, Analysis, and Reporting Technology) status and test the hard drive's physical condition. Best of all, their software can re-map bad sectors to spare sectors. You can find most diagnostics software on the manufactures' website or use the version included in the Ultimate Boot CD (recommended). Cost: Free.
Ultimate Boot CD
SpinRite

Intro screen from GRC SpinRite
SpinRite from Gibson Research Corporation is a magnetic storage data recovery, repair, and maintenance utility. The way it works is quite ingenious. It reads the data from each sector, inverts it, and then writes it back to the drive. It then reads the same sector, inverts the data, and then writes it back to the drive in the original format. If it can read, invert and write to a bad sector, it can clear the bad sector flag and make it usable again. SpinRite also has a feature called DynaStat that can reassemble missing data from bad sectors. Cost: $89.
SpinRite
f83bf1cc-2402-4356-bb6f-4c290c213af0|0|.0|96d5b379-7e1d-4dac-a6ba-1e50db561b04