I install Recuva in my computer, but when I try to verify the "F" disk, the window apeear: Failed to verify the following device F: can't determine system type file. Recuva can't open "F" drive disk, Do I need to format the "F" disk before procedee to verify? My files are audio type and when I tried to open "F" disk in Windows Explorer, the following window message appear: F disk in unformated, do you want to procedee? When this problem apeeared in first time, I rejected and buy Recuva to recovery data files.