Why did you run this update on a MBL DUO? This update is for the single drive MyBookLive…
I’m surprised your DUO accepted this firmware and allowed you to update
You may still be able to get your DUO back up and running following GUIDE 1 of my MBL DUO debricking guide
http://community.wdc.com/t5/My-Book-Live-Duo/GUIDE-Debrick-a-MyBookLive-DUO/td-p/544860