Access / Write Protect on Linked MyBook Drives

I have recently purchased a MyBook World White Light 1TB drive.  I have linked through the USB port an old MyBook Essential 2.0 (1TB) drive. I can see the drives in my Windows 7 “computer” page but I am having access and permission issues and when I try to access applications, especially in a Windows 7 Homegroup shared environment, I get that the disk is Write Protected?  Any ideas?

Also every time I try to access the drive I have to wait while this green bar extends across the top of the screen.  It makes it real slow.  Really slow.

Any assistance would be appreciated.

How is the external (as opposed to the network) My Book formatted? Have you run a diagnostic to make sure it is not damaged? If so what were the results and what program did you use?