Can you afford to lose the data in question?
How much time do you have to start over?
With this in mind, to minimize the impact of a hard disk drive failure:
Perform comprehensive, frequent backups.
Save a copy of the boot-sector and partition-table information.
You should have the following tools at hand to perform hard disk repairs:
A list of the hard disk drive's parameters and the correct CMOS settings required.
A bootable floppy disk with the FDISK, FORMAT, CHKDSK, and MSCDEX (if using a CD-ROM) command files. Adding EDIT or another text editor is handy for tweaking the CONFIG.SYS and AUTOEXEC.BAT files.
Drivers needed to get the operating system running with any primary expansion cards (drive controllers, SCSI card, display adapter, and so on.)
Good cables for the kinds of drives you might have to repair.
CHKDSK or other hard disk inspection programs that are part of the operating system on the drive in question. Be sure to use the right version!
A number of third-party programs are also available for use with older hardware and operating systems. These programs are available at most computer software stores.
CAUTION
When using any third-party programs to troubleshoot/repair a drive, be sure they are certified for the hard disk drive and operating system in question. Use uncertified third-party programs only when such a step is the last resort before discarding the drive. Even then, be aware that the program may cause problems of its own. Keep the software up to date; changes in the operating system or bugs found in the utility can render the product more of a problem than a cure. If possible, back up any critical data before using the software.
Abort, Retry, Fail or Abort, Retry, Fail, Ignore Errors
The most common drive errors begin with "Abort, Retry, Fail," or "Abort, Retry, Fail, Ignore."
When you see any of the following errors, you have a drive problem:
Sector not found reading drive C: Abort, Retry, Fail? Data error reading drive C: Abort, Retry, Fail, Ignore? Read fault reading drive C: Abort, Retry, Fail, Ignore? Invalid media type reading drive C: Abort, Retry, Fail?
These errors are the easiest to fix and can usually be attributed to a bad sector on the drive. When this happens, try the following.
ScanDisk
MS-DOS, Windows 3.x, and Windows 95 and 98 contain versions of the ScanDisk program. ScanDisk performs a battery of tests on a hard disk, including looking for invalid file names, invalid file dates and times, bad sectors, and invalid compression structures. In the file system, ScanDisk looks for lost clusters, invalid clusters, and cross-linked clusters. Regular use of ScanDisk can help prevent problems as well as resolve them. Windows 95- and 98-based computers will automatically run ScanDisk any time the operating system is improperly shut down-that is, when the power is turned off before the system is allowed to complete its shutdown procedures.
Verify the Media
Most SCSI drives have a program built into the controller that will verify the hard disk drive and make repairs if a sector has become unusable or unstable. Boot the PC and watch for a prompt to enter the SCSI BIOS setup (usually CTRL+A). Then choose Disk Utilities and the option to verify or inspect the drive. Do not select the low-level format option. After the program is finished, reboot the computer and see if the problem is resolved. If the disk fails verification, it might need to undergo low-level formatting or be replaced.
CMOS Errors
At times, the system CMOS becomes unstable. This can result in the following error messages:
CMOS configuration mismatch No boot device available Drive not found Missing operating system
Checking the CMOS is quick and easy. It is a good idea to always have a backup of the CMOS data on paper.
NOTE
After boot up, if you receive the message "Strike F1 key to continue," this indicates that your system configuration is invalid and you will need to check the CMOS settings.
Connectivity Errors
Connectivity problems (when something is not connected or plugged in) usually appear when you boot up a computer. Look for the following messages:
HDD Controller failure No boot device available Drive not found
Connectivity errors are overcome by inspecting the entire connection system (including power). You might want to try removing and reseating the controller if you get an HDD controller failure.
TIP
As a computer technician, you should keep an extra controller and cables around. Often, substituting a good cable or controller is the quickest way to solve a hard disk drive problem.
Lost Boot and Partition Information
It is possible for a drive to lose partition information. Look for these errors:
Invalid partition table Corrupt boot sector Non-system disk or disk error
Boot and partition information is stored on sectors and can fail. If the partition table or boot sector is corrupted, the best solution is to restore the data on the drive from a backup copy after repartitioning the drive and reloading the operating system.
