I have an 8gb thumb drive that I wanted to use to transfer video files from my mac to a pc. I’ve formatted the thumb drive with disk utility (FAT), and put the files onto it. When I plug it into the pc, it says the drive needs to be formatted. And if I try and format it on the pc, it tells me it’s only 200 MB. Any idea why I might be having so much trouble? I thought the whole idea of using a thumb drive was to make it easy to transfer files between computers.