Formatting a computer hard drive is always a last-resort effort to pursue only when all other methods of attempting to fix a problem have failed. A formatted hard drive will be completely wiped of all data, including the operating system. The Microsoft Windows operating system comes with a built-in feature that allows you to format a hard drive without having to use a boot disc or installation CD.
Click "Start," then "Control Panel." Double-click on "Administrative Tools."
Double-click "Computer Management" and then click "Continue" when a box pops up. Wait for a new window to appear and then scroll down through the list of options on the left pane. Click on the "+" sign next to the "Storage" option and then click on "Disk Management."
Find the hard drive you want to format in the list of drives in the center pane. Right-click on the drive and choose the "Format..." option from the new menu that will appear.
Choose the "NTFS" option from the drop-down menu labeled as "File System." Leave the "Allocation Size" option at "Default" and then click on the "OK" button to begin the formatting process.
You can only access the format option if you are currently logged into an account on the computer that has administrative access. Depending on the size of the hard drive and the amount of data you have on it, the formatting process could take several hours.
Once the drive has been formatted, the Microsoft Windows operating system will be completely deleted. The only way to continue to use that drive will be to purchase a Windows installation disc and reinstall the operating system.