How can I format my harddrive with my OS without a windows disk?

[dayers2]

I want to install a version of XP one of my friends made, but I need to format my Harddrive first. How can I do this (I have Vista) without a windows disk?

 

[dyyylllaannn]

I'm pretty sure that you can't downgrade to XP from Vista. Sorry, you're out of luck.

 

[iSarah]

You can't be using it on a different computer, without first removing it from the first computer's Hard drive., is illegal, and MS will not allow it.

 

[Tyler]

You cannot reformat a HDD that contains Windows. This is a safety feature so that you cannot delete Windows by accident. You said you don't have the CD, which poses a problem, if you had that XP disc then you could restart your computer, format it and then install XP with that disc. I guess I would try and borrow a disc from someone, or else you could create a new partition that you could install XP on and then later format the partition that Vista is on. Hope this helps you out some.