First of all it's called "Workbench" not "Desktop".
If there an icon there, then it's been recognized, but nor formatted.
I suggest going into SYS:Prefs/, deleting all the tooltypes in HDToolBox.info, then running HDToolBox, and re-partitioning the drive, making sure the first partition is under 4gig.
Then format the "Uninitialized" partition (after rebooting)