How to Diagnose a Computer Hard Disk Drive

Three Methods: Testing a Nonworking Drive  Testing a Working Drive  Using Windows Diagnostic Tools

Your computer's hard disk drive, referred to herein as "drive", is where all of your programs, files, and operating system(s) are stored. The drive is a delicate device, with multiple magnetic-sensitive platters that typically spin at 7200 to 15,000 RPMs. Data on the platters is accessed and modified by the read/write head, which moves back and forth over the platters. These platters are very delicate, and contact with the read/write head is a very bad thing. This article will discuss how to determine if your drive is broken, if you are able to fix it, and how to recover your files. These steps only apply to computer drives, and not those of proprietary devices like the Apple iPod.

Method 1 of 3: Testing a Nonworking Drive

1. Before doing anything to your drive, read the Warnings section below.

2. Determine if the drive is inaccessible because of a mechanical failure or a software problem.

3. If the drive is making strange rattling or clicking noises, turn off the computer immediately. You can remove the drive by taking the cover off of the side of your computer (or the drive bay of your laptop) and using a screwdriver to disconnect the drive from its mounting bracket. Disconnect the cables from the back of the drive and store it in a cardboard box or an antistatic bag. You can fix this mechanical problem yourself if you are brave. Otherwise, do a Google search for computer repair or data recovery specialists in your area. This process is expensive, but can be worth it if your files are very important.

4. If the drive seems to be working normally but appears as unformatted in your computer's BIOS or Windows, you may be able to fix it yourself. If your computer boots into Windows, the C drive is just fine and will make repairing your secondary drive or partition much easier. If your Windows drive appears as an unformatted drive in your computer's BIOS, remove it (following the removal instructions in Step 3) and mount it in a working Windows PC. This could be a friend's computer or an old 2000 or XP machine that you have kept after an upgrade.

5. If you need to attach a laptop drive to a desktop machine or vice versa, you may have to purchase an external drive enclosure that converts your drive interface from PATA, SATA, or SCSI to USB or FireWire. You may need to do this anyway, depending on the age of the computer you are using to fix the drive. Older computers may not support drives from newer computers. Check your drives or the computer's user's manual to be sure.

6. Once you have the problem drive mounted in a computer with a working Windows drive, ensure that you never write data or format the broken drive, as this can cause permanent data loss.

7. If you have only damaged or erased essential operating system files from your Windows drive, the disk can still be read from your repair PC and you can easily recover data from My Documents, etc. Just browse to the files in Windows Explorer and burn them to a DVD or CD for later replacement.

8. Move the drive back to its native computer and reinstall Windows on it. This will reformat the drive and any information still on it will be erased.

9. Once you have a fresh, clean, and fully functional copy of Windows, you can put your files back in their rightful places and get on with the lengthy task of reinstalling all of your programs.

10. If the drive in question is a data drive or a Windows drive that appears as unformatted, you will have to use data recovery software, the best example of which is TestDisk, a free utility that will analyze your drive and recover your data.  Get it at Click here  and unzip and run the program.

11. Follow the instructions in the program or go to http://www.cgsecurity.org/  for more help.

12. Once TestDisk has made your drive accessible again, move it back to your own computer (if you had to move it in the first place) and enjoy your recovered files..!!

Method 2 of 3: Testing a Working Drive

1. Create an image of the disk. Use Norton Ghost or Arconis True Image to create a complete image of your entire hard disk. The image will be the same size as the all of the content of the disk, so it could be quite large. Save this image to an external hard drive or another installed hard disk.

2. Remove the disk you want to test. After making a complete image of the disk, remove it from your computer. Be careful when removing the disk so as not to damage any of the delicate components.

3. Install the disk in another computer. Install the removed hard drive  into a computer that works. Make sure that when you install the drive, you are installing it as a secondary or slave drive.

4. Download HDD Sentinel. This program will allow you to run a number of different tests on hard drives. The test you want is the "Write+Read" test, which will overwrite the disk and then read back the written sectors, looking for bad areas on the disk.

• Make sure that you have the correct disk selected!

5. Repartition and reformat the drive. After the test is complete, use a tool such as Paragon Hard Disk or the built-in Windows Disk Manager to reformat the drive so that you can copy files to it. Restart the computer after the drive has been formatted.

6. Test the disks. The computer you installed the original drive onto should have its own drive as well as the one you installed. To ensure that the hard drive is working correctly, you will be testing a file running from both hard drives.

• First, open a video file from the original disk on the second computer (the one with the operating system). The video playback should be smooth and without errors.
• Copy the same video onto the freshly-formatted disk that you installed from the first computer. Playback this video and check for any distortion. If the video is corrupted or distorted, then your drive is a "zombie" drive, and will always corrupt data when it is used.

7. Install a replacement disk. If your disk is in fact a zombie drive, then you'll need to replace it. Once you've obtained a new disk of equal or greater size than the original, you can use Norton or Arconis to copy your disk image back onto the disk. You can then install the disk back into your computer and use it as you normally would.

Method 3 of 3: Using Windows Diagnostic Tools

1. Open your Computer/My Computer view. Open up Windows Explorer by pressing ⌘ Win+E. This will display all of the drives that are connected to your computer.

2. Right-click on the drive you want to test. Select Properties from the menu.

3. Click the Tools tab. You will see a couple of different options. Find the "Error checking" section.

4. Click "Check" or "Check Now". You may have to enter an administrator password if you are not currently logged in as the administrator.

5. Check any boxes for error fixing. Depending on the version of Windows you are running, you may need to enable error correction. Later versions of Windows will handle all of this automatically.

6. Click "Start". The scan will begin. Scanning the hard drive can take a significant amount of time, and may slow down your computer as you are using it. Try to run the scan at a time when you are not using your computer.

• If any errors are detected, Windows will attempt to fix them automatically. You will receive a report at the end of the scan letting you know what the results were.