If your PC has been unlucky enough to contract a virus, you might want to reformat it. In this article we explain how to wipe your disk clean in Windows
There are many reasons why you might want to format a hard drive, including a clean installation of Windows to get rid of a virus or malware, because you’re giving the drive to someone else, or throwing it away.
Here, we’ll explain everything you need to know to get the job done properly. What you’ll need to format the hard drive depends on a few things, such as whether it’s your only hard disk and if you have a spare PC or not.
You can’t, for example, format the hard drive on which Windows is running. In order to format the disk and reinstall Windows (or another operating system), you’ll need to boot your computer from a Windows installation disc, a USB flash drive or another bootable disc.
Formatting is the process of deleting all the data on the hard drive, but beware of ‘Quick Format’, which leaves all your data in place and makes the drive appear to be empty. A quick format is okay if you have a brand new hard drive, or you want to reinstall Windows, but not if you’re disposing of the disk.
A word of warning: make sure you have successfully backed up any photos, videos, music and other documents from your drive before you format it. Although files can be recovered in some situations, prevention is always better than cure.
Partitions
It’s important to understand about partitions before you start. A hard drive’s storage can be divided up into smaller sections, called partitions. It’s possible to format one partition while leaving the others untouched. While that’s useful in certain situations, if you want to format the entire hard drive and use the entire capacity in one block, you’ll also need to delete the partition information.
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| Quick format |
Windows Vista, 7 and 8 have a built-in Disk Management tool, but the fastest way to format a hard drive is to click the Start button, then Computer and right-click on the hard drive you want to wipe (you can’t format the drive on which Windows is running for obvious reasons). Choose Format… from the menu and a new window will appear with a few formatting options.
By default Quick Format is checked, and you can choose the file system and allocation unit size, as well as changing the volume label (the drive’s name). Typically, you can leave all settings unchanged and click the Start button. In under a minute your hard drive will be formatted. You should choose NTFS as the file system if it isn’t already selected for Windows Vista, 7 or 8.
Windows’ Disk Management
Type diskmgmt.msc into the search box in Vista or Windows 7 and then click on the only result that appears in the menu above, with the same name. This is the easiest way to launch Disk Management, but you’ll also find it in the Control Panel if you search for ‘disk’ or look under the Administrative tools section, where it’s called ‘Create and format hard disk partitions’.
Disk Management isn’t as powerful as a standalone partition management tool, but it’s still useful. When you install a new (additional) hard drive in your PC, you might wonder why it doesn’t appear in Windows Explorer. The reason is because it needs to be initialised and formatted – you can do this in Disk Management.
When the tool loads, it will analyse all your computer’s drives and will prompt you to initialise a new disk that it finds. If your disk is larger than 2TB, you should opt for GPT (GUID Partition Table). This setting also lets you create more than four partitions.
If you don’t see a prompt, look in the list of drives and you should see one that says ‘Not Initialized’. Right-click on it and choose Initialize Disk. Once that’s done, right-click in the hatched Unallocated space and select New Simple Volume. Follow the instructions, choosing how big you want the partition to be (in MB – 1024MB = 1GB), and which drive letter you want (one will be chosen, but you can opt to change it if you wish).
When you come to format the partition, our advice is the same as in the Quick Format section. If you select a size for the partition that’s smaller than the total capacity of the drive, say 500GB on a 1TB drive, you’ll end up with some unallocated space on the drive that you can format by repeating the process you’ve just completed.
Changing a partition’s size
You can use Disk Management to expand or shrink a partition. Right-click on one and choose the appropriate option from the menu that appears. If shrinking, the partition will be checked to find out how much empty space it contains.
It’s a little confusing as the numbers are displayed in MB rather than GB,but you can adjust the amount of space to shrink and the ‘Total size after shrink’ will be updated. You can’t shrink a partition beyond the point where files are located – you may be able to free up space by defragmenting the drive first. Conversely, you can only expand a partition if there’s unused space on the drive. If not, the option will be greyedout.
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| Scratch disk |
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| Initialise Disk |
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| Disk management |
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| Shrink partition |
