I have a WD MyBook Essential (3TB) attached to my Apple Airport Extreme. The USB Drive has 3 partitions, 2 for Mac backups, and one for video storage. I can see the Airport Express as a Network Share on the WD Live, but when I try to access it, it sez (There is no media in the current Folder). I can fully access the USB Drive from my PC, as well as my MacBook, and even the Plex Media Server on my iPad.
Any suggestions?