In 2011 I had problems with Samsung Kies. Back then I thought it would be because of gravel that not all files have been transferred to the SD card. Even after direct copying errors occurred. However, Windows XP did not report any errors. It was not until Windows 7 is reported when copying data of unknown error. Check disk claimed everything would be OK SD card was also tentatively on NTFS formatted, same error message. With Windows 8, the same error.