Can't access wd2go on a macbook running OSX 10.5.8

Are you trying to connect using WD2go from the same network that the drive is attached to? I have never had any luck doing that.

Someone else is having the same issue

http://community.wdc.com/t5/My-Book-Live-Duo/can-t-access-the-drive-through-wd2g/td-p/475694