Wd studio book ii hd replacement

hi,

I have a studio ii book for mac. It was making an awefull noise and  it came with 2 x 1tb green drives. 

I have purchased a 2tb wd red drive with the look at getting another 2tb at a later stage.

It doesnt seem to let me have just 1 drive in the enclosure. When i go to drive utility it either doesnt recognise it or wont format it. 

Can someone help?

Thanks

Hello,

The WD My Book Studio II supports only WD Green drives.

Check this link for more information.

How to dismantle a My Book Studio Edition II or Mirror Edition to replace a hard drive