Microsoft have now released an official driver update for Windows XP, that allows one to access exFAT partitions. The exFAT/FAT64 filesystem is only supported for Windows Vista/2008/CE 6.0, and it is not possible by default to access exFAT partitions from other versions of Windows.
It is a proprietary file system that was introduced with Vista SP1. Microsoft have created the exFAT filesystem to better support flash drives.
