format c: /s

Note that formatting your drive or drives necessitates that you have valid partitions, or at least one "active partition" on your physical hard drive. If you're starting from scratch you'll need to run fdisk first.

Also, some boot disks might not have included. If you don't have it you can download it here.
Unzip it and copy it on to your boot disk.

To format your hard drive you'll need a boot disk. If you don't have one and Windows is still operational, go here startupdisk.html for instructions as to how to make one. If windows is "not accessible" to make one, call your local computer store or drop me an E-Mail and I might be able to help you.

Caution! Following this procedure will erase all data of your Hard Drive!

To format your hard drive: ( Some boot disks don't have included. Get it here )
1. With the machine turned off insert the boot disk into your A: drive, and leave it there until the end of this process.
2. Push the power switch and let it ( hopefully ) boot to an A: prompt. ( A:> )
3. If you're sure you want to proceed type: "format c: /s" ( without the " " ) The "/s" makes the drive a bootable drive by copying the file to C: at the end of the procedure. You will get a warning saying that this action will erase all data on the drive. If you want to proceed press "Y" and move on. If you're formatting a partition, other than C:, or an other physical drive, leave out the " /s" when you type "format D:" or "format E:" When prompted for a "Volume Label" name your drive anything you like, or just hit "enter" for none. You can change it later if you like.

Now remove the system disk from the A: drive and reboot. If all went well it will boot normally to the C: prompt. If it didn't, you may have problems with the primary partition. Go here fdisk.html to see how you might fix it.

A note for Windows XP Users:
During the installation of XP you'll be offered the options for formatting your Hard Drive.
There is no need to do it before that. Windows XP is very capable of formatting the drive for you.

In Windows XP: If you need to format the C: Drive to do a clean install, just put the CD in your drive and reboot the machine. It will eventually offer you the option to delete the C: partition and then create a new C: partition, format it, and install on that new partition.

Windows 7 same as XP: Just put the DVD in the drive and follow the prompts.

Low Level Format: If you need to do a low level format on your drive you can download a good tool here:


Still having problems?
Call for a Free initial phone consultation.
The Pittsburgh PC Help Desk


Return to PC Help Desk
Return to

Leave Comments and Ask Questions