I have downloaded and installed the driver update for XP (KB955704) - still it does not detect the harddrive. I have restarted the machine ofcourse. On my disk management the hard drive is still showing as 'unallocated'. Can you help?
Did this problem occur after a XP reinstall?
Or did drive come from another system with latter windows?
Why are you using exFat?
Is there any data on it?
Internal or external drive ?
If you can extract data on another PC
Repartition and format as NTFS unless very good reason
A gparted live Linux cd image may be able to read the disk and check it is working not damaged http://gparted.org/features.php