I have a three-year-old Buffalo 1TB external hard drive. It has always worked fine and hasn't been used very often (once every few months for back-ups). It contains thousands of files totalling maybe a few hundred G. This week my Macbook refuses to recognise the existence of the hard drive. The hard drive has power, is motoring, but there is no icon on the macbook, nothing in disk utility etc, and no sign it exists. I have tried both the USB ports available on the macbook. The hard drive has a 1 SATA drive. The macbook is running OSX 10.5.8. Is this a software update issue or is this a self-destruct thing?