This is a long one:) First is 250 GB showing is correct. We won't go into that now as not important. I would use Windows to format the card to fats 32 (4 Gig max folders) quick format. Use your laptop wisely and install your music folders a few at a time. The volume of music files in 1 Gig of data is huge so do it in stages is my advice. Folders no bigger than 4 Gig. You do create folders for your music or data?
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