Norton Ghost Help

I've got a macbook pro that I have partitioned with bootcamp to run Windows XP. (2 partitions) I want to clone my current hhd onto my larger external and then replace it. When I run Ghost and use the Copy My Hard Drive tool I am unable to see my hhd connected by usb. The external HD also does not show up as a drive on the My Computer window but I can view it under Disk Management window and is labled unallocated.

 

What am I doing wrong here?