exFAT (Extended File Allocation Table), (also sometimes referred to as FAT64) is a proprietary file system suited especially for USB flash drives, introduced by Microsoft for embedded devices in Windows Embedded CE 6.0, in their desktop operating systems. exFAT can be used where the NTFS file system is not a feasible solution, due to data structure overhead, or where the file size or directory restrictions of previous versions of the FAT file system (32 GB drive and 4 GB file size limitations) are unacceptable.

It comes pre-installed in Windows Vista (SP 1), Windows 7 or Windows Server 2008. But exFAT isn’t native to Windows XP (Windows Server 2003 also) – which the vast majority of you are probably still running. Microsoft has released KB955704 to address the issue. You can simply download the package and install to get exFAT support installed in your XP machine and you’ll be able to seamlessly work with exFAT partitions in XP.