Please Help:TC4400 tablet pc touch screen does NOT work at all

I recently installed a new OS on an HP tc4400 which the user had run C:\format. He gave me a copy of what i was told was the xp tablet OS. I installed all drivers from HP.com and the everything but the touch screen works. Does anybody have any ideas or know where i can get the software/drivers to make the t.screen work (any more not listed on HP.com). Or do I simply need a copy of the oem XP tablet OS disk from HP? ALL RESPONSES APPRECIATED. TIME CRITICAL. THANKS ALL.