Yesterday I used FDISK for the first time, under Doc's guidance. I apparently formatted my new external HDD into a primary, extended and 2 logical partitions for use primarily as a deposit for Ghost images. I subsequently have read advice on this website that when using external HDDs it is best to backup a whole disk at once rather than partition by partition. I therefore returned to fdisk to re-partition my HDD to create a partition large enough for an image of the whole of my internal HDD (which is 60GB).
Despite the fact that I created the logical drives yesterday, and can see them in WindowsXP, fdisk fails to find them. It acknowledges the existence of the primary and extended partitions, but reports that there are no logical partitions on my external HDD.
What's going on, and how do I get round it?

Since you are using XP, you can manage your partitions (again be VERY CAREFUL) using the XP disk manager:

Right Click My Computer/Manage
Maximize the window
Select "Disk Management"
Select the Volume (disk) you want to manage
Right click and you have options to delete a partition, format as NTFS etc.

Just be sure you have highlighted the CORRECT drive!