the only format accepted by the autel card is fat 32.  The biggest card size you can safely use without running into issues is 32gb.  Tried to format a 64gb card to fat 32 and windows will NOT allow.  There are programs out on the web that claim to format a 64gb card and bigger sizes, but most do not work.  Good Luck.  Stick with 16gb or 32gb card and you will have no problems.