At first I had problems with it not thinking that it was plugged in (overloading the USB port on my computer), but I foregave it. Then I realized WHY it was having the issues, every time I tapped on the top of the unit AT ALL, it rebooted itself. This on a MAC is bad, especially when importing 200 gig of information :(Needless to say my faith is shaken and I will be asking for a refund to buy a more stable unit.