How to Fix Bad Sectors on a Hard Disk

By Techwalla Computers Editor

The minute your computer's hard disk starts to act flaky, make sure you have an up-to-date backup. Then you can do some simple diagnostics and repairs. Both Windows and Mac OS come with built-in hard-disk utility software that scans your hard disk for errors and attempts to fix them.

For Windows

Step 1

Double-click on My Computer to open the My Computer window.

Step 2

Select the disk that you want to diagnose and repair.

Step 3

Choose Properties from the File menu. You should see the Properties window for the drive that you selected.

Step 4

Choose the Tools tab.

Step 5

Click the Check Now button under Error Checking Status.

Step 6

Depending on your version of Windows, choose either "Thorough" or "Scan for and Attempt Recovery of Bad Sectors."

Step 7

Click on Start.

Tips & Warnings

  • Third-party hard-disk utilities do a more thorough job of diagnosis and repair than the software that comes with Windows or Mac OS, but they work much better if you install them before you have a problem.