2 Replies Latest reply: Apr 21, 2013 9:21 AM by wham1000
Nick Howard Level 2 Level 2 (210 points)

I'm trying to install a Western Digital caviar black 2TB as the fourth internal drive in an early 2009 MacPro running 10.7.5.


I'm using Disk Utility to format it - or trying to.


I click 'erase"


Helpfully, it tells me that this disk is unformatted.


I click "erase"


I get:


"Disk erase failed with the error:

Couldn't open device"


Could anyone tell me how to deal with this?