I purchased a 64GB micro SD card for my Samsung SM-G361F mobile phone and am having a strange problem. I have converted the card to exFAT32 and when I transfer exactly four 1.8GB MP4 files to the card they work ok. When I transfer a fifth 1.8GB MP4 file it seems to take longer to copy to the card via windows8 and doesn't work whatsoever when I try it out on the phone. I have even formatted the card to NTFS but that totally fails to read on windows at all!? Does anyone know what the problem may be? Im thinking the phone does not support a 64GB card whatsoever or perhaps I have a faulty card?