Having just received Leopard I was very excited but when I put the disk in my macbook to install it I got the following message. ''You cannot install Mac OS X on this volume. To enable installation on this volume open Disk Utility from the Utilities Menu and repartition this disk as 'GUID Partition Table'. Note: You will lose all data on this disk by repartitioning it.'' Please can somebody help me because my HD had a fault a few months ago and I lost everything, so I really don't want to have to start from scratch again with all my work. Thanks a million!