How to Spot a Failing Hard Drive
Everybody who uses computers regularly is likely to experience either data loss or a
failed hard drive (or both, which is more common than you think!) at some time. Hard
drives store data in "sectors" (if using the FAT16 file system, used with much older
operating systems such as DOS) or in "clusters" if used with FAT32 or NTFS file systems.
Hard drive recovery is possible if you catch a failing hard drive early enough before it
Hard drive maintenance is important for maintaining a hard drive's longevity and it's
up to you to ensure you do some hard drive maintenance regularly (once per week or month
at a minimum) - you'll be surprised how much upset this can save you later down the line
if you persistently stick to this maintenance regime - set it up to do it at a late time
if you leave your PC on at night - you won't even notice it then.
Hard drive maintenance can be broken down into two distinct functions: checking the
disk occasionally for failed clusters and keeping data organized on the drive so that it
can be accessed quickly. Having data available in the right place on the hard drive makes
your hard drive's job so much easier and therefore it doesn't need to work as hard to
provide the data that your operating system needs - thus prolonging its working life.
Hard drive problems fall into three broad categories:
• Data corruption and;
• Dying hard drive;
Power surges, accidental shutdowns, corrupted installation media and viruses are among
the causes of corrupted data in individual sectors / clusters. These errors usually show
while Windows is running. If core boot files become corrupted, you may see text errors
such as "Cannot find COMMAND.COM," "Error loading operating system", or "Invalid BOOT.INI".
Older systems may generate a sector not found error. The first fix for any of these
problems is to run an error-checking utility, such as Spinrite from Gibson Research. If
you get the "Trying to recover lost allocation unit" error, this means that the drive has
bad sectors. If this happens to you, then it's definitely time to start thinking about
replacing your failing hard drive - and quickly.
If you get an error which says that a particular file is missing for Windows to run or
function properly,then to replace a single corrupt file, you must know the location of the
numbered Windows CAB (cabinet) file that contains the file you need and how to extract the
file from the CAB file. Use the EXPAND program with Windows 2000/XP to get a new copy of
the desired file from the CAB file on your installation disc, which you should have for
installing Windows in case of emergency. EXPAND searches all CAB files to find the file
you specify, and then expands it and places it in the C: folder. To find out more on how
to use EXPAND, take a look on a Google search.
Thankfully for the uninitiated, almost all hard drives today have a built-in error
correction code (ECC) that constantly checks the hard drive for bad sectors / clusters. If
the drive detects a bad sector as it operates, it then marks the sector as bad in the
drive's internal error map so that it's invisible to the operating system and therefore no
data gets written there. However, if the ECC finds a bad sector with data already within
it, you will get a corrupted data error when the computer attempts to read the bad sector.