I have just bought a macbook and i plugged my external harddrive that I have been using for years on my laptop (microsoft) into mac and it worked fine. I had to convert all my music folders tho which took hours as i have a huge amount of music. i then plugged it back into my old laptop to check sth and when i tried to open it, it said i needed to format it, but obviously i dont want to do that. so i then plugged it back into my mac which then said it could not read the device! Help - how do i get into my external harddrive!?!