I'm working on an iMac that has Vista (yuck!) installed on the hard drive. When I boot up and external with OSX, the internal partition is not recognized by Finder. Disk Utility claims its HFS+ but will not mount it. When I boot the machine with GParted, it also claims the partition is HFS+. It looks like Vista was installed over the OSX partition and the GUID still thinks its HFS+. Is there a way to correct this so that it shows up as NTFS? I would like to use GParted or WinClone to back up the partition.