Don't know about 64 gigs cards, I formatted my 32GB with exFAT in a card reader, but the phone required it to be FAT32 to be able to use it.
Recently I have bought a 64gb sd card, but it doesn't work well. My computer usually say the sd card has been removed but it isn't. Also sometimes it self-deletes files. Why is that? I have formatted the sd card twice. Now its on exFAT.
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