When running Disk Defragmenter a message appears telling me the task cannot be completed because the disk needs to be repaired and I should run ScanDisk. However, ScanDisk seizes up after a few minutes of operating. I have followed your previous advice about closing all non-essential applications while running the ScanDisk and Disk Defragmenter but this does not help. The machine is about 4 years old and seems to be running more slowly than previously - do I need to replace the hard disk? The computer is a Pentium II 233 MHz laptop running Windows 98.

If you experience problems running Disk Defragmenter or ScanDisk in normal windows, the neatest way to run these utilities is through Safe Mode. Restart your computer and when the ‘Starting Windows 98′¦’ message appears (just before the Windows splash screen) press the F8 key. In the boot menu, select ‘Safe Mode’ and press ENTER. Once Windows has finished loading, try running ScanDisk.

If there are still problems, try running ScanDisk through DOS. Reboot your computer, press the F8 key to display the Windows boot menu. In the menu, select ‘Command Prompt Only’. Once the system has finished loading and the C:> prompt is displayed, enter the following command to change directories to the directory containing the ScanDisk program:
cd Windows
cd Command
The prompt should now show C:WindowsCommand>. To run ScanDisk, type the command:
scandisk /all
This will scan and repair all drives. Other switches you can use are ‘/autofix’ to repair problems without prompting and ‘/surface’ to run a surface scan (be aware: this could take a long time). These switches do not need to be used individually, you can use them in a combination (e.g., scandisk /all / surface /autofix).