WD 1TB drive on Mini won't mount on MBP?

Ok, so both machines are running 10.6.7, same 2.4 intel cpu.

The Mini has 3 USB HDD's, all working fine, mounted, etc.

On the MBP sidebar, 2 out of the 3 are mounted, working fine. The one I can't get to mount is the WD 1TB My Book(the newest drive of them all, btw).

Any ideas?

?Have you gone into the mini and shared that new drive?

Yes. And it's not new. I've had it for almost a year now.