Format My book essential- use the driver for MAC and PC!

WD External Drives External Drives for Mac
2

you can use this tool and you won’ have to format

Catacombae - HFSExplorer

otherwise you can format with the steps bellow

http://wdc.custhelp.com/app/answers/detail/a_id/291/session/L3RpbWUvMTM1NDU3MjE2Ni9zaWQvdEpFeXlSY2w%3D