I have a 16gb usb thumb drive. Halfway through saving a file there was an error and since then it wouldn't mount on my mac. It will on windows pc at work, and when XP is running on the mac in parallels. I reformatted it using disk utility (FAT32), and it still wouldn't mount. I formatted it again using NTFS and it mounts ok. I do not want the disk in NTFS, so when I reformatted back to FAT32 it wouldn't work again. Any thoughts?