XP Pro issue for New C drive

I have to install a new C drive on a computer in our business and discovered that this was one that I cloned the HD from another computer it had replaced and I had installed an upgrade of Pro on that. Anyhow, I do not have the original xp but do have the Pro Upgrade. This is in a business with four other computers running Pro, but each loaded as OEM. I probably do have some old ME or 98. I don't want to clone the drive that I am removing because I think that is the cause of some problems that I am having. Any thoughts would be grateful.

 

Just install from the XP Upgrade disk that you have. It will look for a previous installation and when it can not find one will prompt you to insert a disk. This is when you would inert your old OS disk.