I bought a barracuda internal drive and a external case for it and it seemed to be working fine but all of a sudden OS X doesn't recognize it. It has a firewire connection and the blue light is on the case like normal. I tried using a USB 2.0 connection too and the external hard drive whirrs a little but it doesn't see that either. It doesn't show up in disk utility either. What steps should I take to try and troubleshoot this? Thanks for your help!