HOW CAN I CHECK FOR HARD DRIVE DAMAGE?

How can you tell if your hard drive is damaged before it completely crashes? It's important to detect hard drive damage before it grows into a catastrophic failure. Here's how to check "under the hood" of your hard drive for signs of damage...

A completely "dead" hard drive will have to be sent to a data recovery specialist, and they don't come cheap. The other alternative is to kiss the data on that hard drive goodbye. (If you didn't make a backup recently, see my related articles about Online Backup and Backup Software.) But it needn't come that traumatic point if you check for hard drive damage regularly.

Physical damage to a hard drive often starts with bad sectors - small segments of the magnetic disk that can no longer be read, written to, or even found by the operating system. One bad sector tends to give rise to many others because it disrupts the read/write processes. Bad sectors also cause excessive wear of read/write heads. So your first line of defense is to check for hard drive damage at the sector level.

Every operating system can check a hard drive for bad sectors. In versions of Windows prior to XP, the DOS utility CHKDSK was used at the command line level. Later versions of Windows use this procedure:

• Open the Start Menu and click on My Computer
• Right-click on the icon representing the hard drive in question and select Properties
• On the Tools tab, click the Check Now button under "Error-checking"
• On the following popup window, check the box labeled "automatically fix errors" and "scan for and attempt to repair bad sectors"
• Click OK

You will have to restart Windows because the error-checking utility cannot run while Windows is running. The tests and repairs will take a significant amount of time on a large hard drive; go to lunch or happy hour. When the tests for hard drive damage end, Windows will restart automatically. A report will be available after the error-checker does its job.

Mac OS X users need their Mac installation CDs to check for bad sectors. The install disk you use must correspond to the version of Mac OS that you are running. Additionally, Mac users should run a cache-clearing utility such as Cocktail or Yasu before they check for hard drive errors. Here are the steps to follow:

• Start the Mac from the install disk
• After the Installer window opens, open the Disk Utility
• Select your Mac OS X boot drive from the list of drives that appears
• If you do not see "Verified" in the S.M.A.R.T. field, you have some hard drive damage.
• Click the First Aid tab in the Disk Utility window
• Click the Repair Disk button

If Repair Disk found and fixed errors, it will tell you so. If it finds other problems such as a damaged volume record, follow its instructions to attempt to repair the problem.

Sometimes problems with hard drives originate outside of the hard drive itself. If you are experiencing intermittent read/write failures, check the cable connections between your hard drive and motherboard, and between the hard drive and its power supply. Expansion and contraction during on/off cycles can cause connectors to loosen. Read Is My Hard Drive Going to Crash? for more telltale signs of impending hard drive doom.

Hard drives are not expensive to replace these days. You can recover almost 100% of your data onto a new hard drive if you stick to a regular backup schedule. Do you have something to say about checking for hard drive damage?