If you are selling or recycling the computer and do not care about keeping Windows XP, use a bootable "nuke" tool. This is the most secure method because it overwrites the entire physical drive.
This only works if you have multiple hard drives installed and you want to wipe a secondary drive (not the one Windows is installed on). how to wipe hard drive windows xp
: Go to Control Panel > User Accounts , create a new administrator account, then log out of your old one and into the new one. If you are selling or recycling the computer
On a working computer, download the ISO image of DBAN. Use a program like Rufus or UNetbootin to write this ISO to a blank USB flash drive (or burn it to a CD-R if the XP machine lacks USB boot support). : Go to Control Panel > User Accounts
A Final Format: The Proper Method to Wipe a Hard Drive Running Windows XP