If I'm reading this right, and I think I am, you had windows xp pro, and downgraded to xp home ? Now you don't mention formatting the drive because you kept all your stuff, and now in device manager it show's as a foreign device ? So do you have 2 hard drives in the machine ? Master and slave settings are usually controlled by the system's bios. A drive in sata 1 will be master and a drive in sata 2 will be slave for example. The drivers for the sata controller must be installed for it to be recognised at all, if they weren't then there would be a yellow question mark on sata controllers in device manager.