I want to copy the music files on one micro SD card to another. I'm thinking it will be easy. Two MAC's and a PC later and I guess not. None of these computers can complete the task of downloading the files from the full SD card to a folder on the computer. I start getting multiple different "unable..." and "error..." type messages within minutes. What is the "right way" to do this? Cards are 200GB and 256GB SanDisk if that matters. ExFat or Fat32.