I have only one partition called
C, that drive holds the operating system and all the documents.
I don't have a CD-ROM hence I can't use the installation CD.
Is there any way to format the drive or otherwise completely wipe off everything on it?
It's unclear from your question whether you mean that you don't have the installation CD, or if your computer simply doesn't have a CD drive at all. It's also not clear if you just want to wipe the drive, or also want to reinstall Windows.
If you want to format drive C:, just install Windows 7 (or XP) on another drive (eg D:) then boot into Windows 7, go to 'My Computer' and right click on drive where XP is installed, then click on 'Format' and click 'Start'. Drive will be formatted!
You should get a bootable USB flash Windows XP installation.
You can create it on another PC with CD-ROM http://www.ocia.net/articles/xpflashdrive/page1.shtml
Do not forget to backup useful information before formatting.
If you want to just format it but don't want to reinstall another Windows, you can do the following (there are other ways) :
1) In some other machine (unless you have yet active your Windows, would be better there) make a bootable CD or DVD. You can do it with many tools, one that comes to mind is CDBurnerxp (there are many other solutions, like BartPE)
2) Ideally copy the needed console commands to that CD. That is, the files for format, and probably fdisk. They're found at your /system32 folder of your windows. If not possible, copy them to some device you will be able to read from console. (those great old floppy disks...)
3) from the device where you have these files, type format c:
You have a list of console commands in Windows here.
If you have a sort of not totally devastated installation, you yet might have the ability to hit F8 key when starting the machine(hit it several times once you here the "bip" of your machine when booting). There you can choose to boot in console mode (can't remember exactly how it calls it) . If you had copied the format etc files to some device (ie, floppy, usb stick if booted that way and have it available at your bios) you can type that unit (ie, a: , intro) , then type format c: and follow instructions.
With just a windows CD is a matter of boot in repair mode and use the command...
edit: sorry, crossposted with RubyWedge.
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