Someday the internal hard disk of your PC or Macintosh will fail-- it's not a question of "if" but of "when." The consequences of a disk failure are unpredictable. In some instances, you'll be able to restart your drive relatively easily and suffer little or no data loss. In more severe cases, you'll have to spend much time and effort reconstructing the contents of your hard disk. And in the most severe cases, both your drive and the data on it will be irrecoverable. Keeping your system fully backed up at all times is, of course, the best defense against potential data loss and the attendant anxiety.

The information here is intended to help you diagnose the cause of a disk failure and offer some suggestions for recovering your disk and its contents. Some familiarity with your computer and its operating system is assumed. If the procedures described here fail to recover your disk, we recommend that you consult a service technician at an authorized computer repair service.

Viruses and disk failure

A computer virus can cause symptoms similar to those that signal a disk failure. For example, on a PC you may see an error message, and a Macintosh may "hang" after it starts to boot. If you don't have antiviral software installed on your system and have used floppy disks that could have carried a virus from an infected computer, check your system for viruses. Use the software to look for and eradicate any viruses that may be present.

 PC Compatible systems

Assuming your system is virus free, you'll know your hard disk has failed if you see one of several possible error messages on your screen. Some of the most common ones are

• "Disk Error Reading Drive C"


• "Boot Failure Drive C"


• "Invalid Command Interpreter"


• "Non System Disk or Disk Error"

A disk failure can be hardware- or software-based. A preliminary diagnostic procedure that requires no special equipment or software will immediately suggest which it is. Boot from a DOS system diskette, either your original or a backup copy. Be sure to use the identical version of DOS (with the same version number and from the same manufacturer) that is currently installed on your system. Try to change to the C (hard) drive. If you don't see a C: prompt, you probably have a hardware failure. If you do see the C: prompt, it's a software problem.

If you suspect a hardware problem, the first step is to take your PC to a computer repair service for further checking. If testing confirms that the drive is damaged, you have the choice of replacing the drive (and losing all the data on it) or sending the drive to a data recovery service. Service technicians there will dismantle the drive in a "clean room," put its platters into an identical drive, and try to restore the data to a new hard drive.

If you can see the C: prompt, the system files may need to be replaced. Damaged system files are a common cause of disk failure. Start by copying all the data files for which you don't have backup copies to floppy disks. This is a precaution in case your hard disk cannot be revived. Don't bother copying application files--you'll need to reinstall them from originals if you recover your drive.

While copying files, you may get one or both of the following error messages:

• "abort, retry, fail"--this indicates that you can't continue copying the current file (or one of several files if you are using XCOPY) because it is damaged. Press "a" to abort, return to C:, and copy the next file.


• "abort, retry, ignore, fail"--this indicates that the file currently listed on screen is damaged. Press "i" for ignore and go to the next file.

Note the names of the files you couldn't copy, so you can later try to recover them or copy them from old backups.

Next, replace the DOS system files on your hard drive. At the A: prompt, type sys C:. You'll see the message "system transferred" when the system files have been transferred from the floppy disk to the hard disk. Also copy the command.com file to the hard drive. Then try to reboot your machine without the floppy DOS disk in drive A. If it works, you should still have your system checked out at a repair service.

Once you've had your system checked out, you can start to restore files from any backups you have and/or recover any damaged files you weren't able to copy to floppies earlier. There are several commercial file recovery utilities on the market for this purpose.

If your system didn't reboot without the floppy DOS diskette, you may need to reformat the hard drive. Subsequent recovery attempts will then be more time-consuming. Before taking this step, the CRC recommends you have a service technician evaluate your system.

Staying out of trouble

Follow these steps to minimize the effects of a disk failure and protect your system:

• Always back up all your files, including fonts, desk accessories, config.sys, autoexec.bat, and other customizable files.


• Don't ignore warning signs. If you have unexplained system or application crashes on a Macintosh, check first for a virus, and then have your system checked out at an authorized dealer. Likewise on the PC side, if your system seems slower or you get frequent "abort, retry, fail" messages, first check for a virus and then have your system checked out.

Data recovery Software & Services

Stellar Information Systems Ltd

Ph: 91-124-5045819

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