Bad Sectors

Source

A bad sector is a small area on the disk drive that is reporting errors and cannot be accessed properly. New bad sectors, sometimes called grown defects, are often caused by some kind of physical damage. If a file or folder uses this sector, then the file is incomplete or corrupt because the bytes are not readable.
Bad sectors can also be reported if the signal between your drive and host adapter is being misinterpreted.
Bad cables can cause this. Consider replacing your Serial ATA cable, which is an easy first troubleshooting step.

Correcting Bad Sectors
SeaTools is available from Seagate for the reparation of bad sectors. It is available in two programs.

• Seatools for Windows. (Please see here for a tutorial on its usage.)
• Seatools for DOS. (Please see here for a tutorial on its usage.)

Seatools
for DOS can scan all sectors for physical errors (but not logical errors), and if it finds a bad sector, it will prompt you to click to repair it manually. Seatools for Windows will notify you that the bad sector exists and will point to a third-party tool to repair it.
(Please note that Seatools is for PC only. Click here for information on MacOS.)

If you have bad sectors that contain data there are several options available from other vendors.

Windows Vista/XP/2000 contains an error-checking utility for hard drives.
To open the error-checking utility in Windows Vista, follow these steps:

1. Click on the Windows icon in the bottom-left of your screen.

2. Click on Computer to open it.

3. Right-click on the hard drive that needs repair (ie, Disk C: or E:).

4. Choose Properties.

5. On the Tools tab, click Check Now in the Error-Checking Status area.
   

6. In the Check Disk dialog box, select the Automatically Fix File System Errors check box, select the Scan For And Attempt Recovery Of Bad Sectors check box, and then click Start.

To open the error-checking utility in Windows XP/2000, follow these steps:

1. Double-click My Computer, and right-click on the hard drive that needs repair (ie, Disk C: or E:).

2. On the shortcut menu, click Properties.

3. On the Tools tab in the Properties dialog box, click Check Now in the Error-Checking Status area.
   

4. In the Check Disk dialog box, select the Automatically Fix File System Errors check box, select the Scan For And Attempt Recovery Of Bad Sectors check box, and then click Start.
   

See image below:

(View Windows help on detecting and repairing disk errors for more information.)
MacOS 10.x's Disk Utility includes a tool called Disk First Aid. To access it:

1. From the Desktop, choose Go from the top menu bar.

2. Choose Utilities (or Applications and then Utilities if necessary).

3. Choose Disk Utility.

4. Click on the hard drive to test on the left, so that it is highlighted.
   
   Click on image to see larger version:
   
   
   
   

5. Click on the First Aid tab and choose to Repair Disk.

6. The tool will automatically display its results after the test is complete.
   
   Click on image to see larger version:
   
   
   

Steps to prevent further bad sectors.
Improper handling of the drive is the most common cause for bad sectors. See our handle with care videos for more information on how to properly handle a drive.