My Book Essential 2.0 has got 3 partitions under Vista and worked well. After upgrading to Windows 8 only one of the partitions (logical drive) was shown up but not 2 others (1. Section). At both the loaded und unloaded sections were zero wenn checked under "Properties". Microsoft Support advised to download the driver from manufacturer. I tried it from your internet support but after downloading the programm couldnot be installed, even tried twice. (may be not suitable for Windows 8)
What is the model number for the unit you have?
Model No: WD6400H1U-00
Yeah, that drive must likely will not work
not sure WD will be releasing drivers for an obsolete drive