SDXC/microSDXC cards and 256GB CompactFlash cards are formatted natively in the exFAT file system. Flash Drives may also be formatted in exFAT. The operating system must support the exFAT file system in order for these devices to function properly. You may need to update the operating system on your devices to recognize the SDXC/microSDXC cards.
Operating Systems that Support the exFAT File System
NOTE: Some Host devices may NOT support SDXC cards. SDXC/microSD cards CANNOT be used with Windows 98, Me, 2000.