Comment 19 for bug 1239087

(Hmm, the drives have

   can_stop=1
   start_stop_type=shutdown

so everything should be good. My guess is that it's the NTFS partition that is the culprit. Specifically, unmounting it via udisks somehow fails.)

If you manually unmount the partitions, does powering down the drive work? Specifically, try this

 1. Unmount all partitions using Disks
    - if that fails, try 'umount /dev/sdXN' from a terminal. Does that work?
 2. Press the "Power off" button in Disks when everything has been unmounted.

Does that work?

Also, please include all messages from udisks from syslog (e.g. /var/log/messages or similar) when pressing the "Power off" button in Disks. It should contain some useful info.