Fixing Bad
Sectors And Lost Allocation Units
There are two main
tools included with Microsoft DOS 6.2x that that allow you to
check for and repair bad sectors or lost allocation units.
These are: Check Disk <CHKDSK> and ScanDisk <SCANDISK>.
In versions of DOS prior to 6.x, the only tool available for
correcting file allocation and sector problems was to run the
CHKDSK program. CHKDSK by itself checks the status of your
hard drive and reports errors but does not correct any
problems. In order to correct possible allocation or
cross-linked file problems, you need to run CHKDSK with the
/f switch. To run the Check Disk program, type:
chkdsk/f
and press enter.
With the introduction
of DOS 6.x, Microsoft added a new tool to aid in the repair
of these problems. ScanDisk is a very powerful hard disk
utility similar to some of the 3rd party programs such as
Norton Disk Doctor and PC-TOOLS DiskFix. If you are using DOS
6.x, we recommend using ScanDisk instead of ChkDsk. To run
the ScanDisk program, type:
scandisk
and press enter.
If there are any lost
allocations or bad sectors you will have the option to fix
them.
If it is determined
that the hard drive needs formatting, it is always best to
run one of these utilities before doing so. If you are
experiencing random lock-ups or other strange problems, it is
possible one of these utilities will correct the situation.
It is also a good idea to run one of these utilities about
once a week to ensure the best drive maintenance possible.
Another hard disk
maintenance utility, called DEFRAG, defragments your hard
drive. As you use files on your hard drive, the system does
not always write the information back to the original spot.
This results in file fragments being located across the hard
drive instead of right next to each other. As fragmentation
increases, the probability of lost clusters or cross-linked
files occurring increases. The DEFRAG program brings all the
pieces back in logical order by putting all the file pieces
back together. We recommend running DEFRAG at least once a
week for normal usage. You may want to do this more often if
you are continuously adding, updating, or deleting files from
you system. To run DEFRAG, type
defrag
and press enter at your
C:\ prompt.
Each of these programs
have various switches that modify the way the program works.
An easy way to lean more about these programs is to use the
online help supplied with DOS. To use help, type:
help
and press enter from
the DOS directory. To receive help on a specific command you
can add the command name after the word help. for example
type:
help scandisk
and press enter. This
displays the help screen for the ScanDisk utility.
You can also receive a
brief summary and available switches by typing the command
followed by a /?. For example, typing:
chkdsk/?
If you are using DOS 6.x,
the help summary recommends that you use ScanDisk instead of
ChkDsk as it is better at detecting and fixing potential
problems. The system displays the same recommendation when you
run ChkDsk on when running under DOS 6.x.
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