i have bought a new 64G flash drive and it is functioning for the first 2 days. after that, it show " the disk is not formated" notice when i try to access my flash drive. i have try to format it by clicking ok but it does not work. i have also try using computer management, VAIO soft recovery manager, Kill disk and other files recovery software but it still doesn't work. I can detect the 64G capacity under the computer management, but it does not show as NTFS file. i have check the flash drive and it show as RAW file system under the properties.