MY BOOK LIVE can't Connect to iMac 2008 (OSX 10.11.6)

My MyBook Live 2TB drive seems to be reading/writing (?) data forever. The green light is flashing almost continuously, and has been for hours. (It’s as though some-one has remote access to the drive.) It was flashing a whitish green for days, at which point I finally gave up and turned off the power since I couldn’t shut it down any other way. Is there a way to diagnose errors, etc. on the drive if the only connection is through Ethernet? What diagnostic software would you recommend since Disk Utility doesn’t see the drive? I have MyBookLive Set-Up, MyBookLive Dashboard & MyBookLive Learning Center, but none of these connect to the drive - Dashboard tries, but times out. Thanks!

Flashing green power LED indicates that unit is performing read or write commands to/from the Hard Drive Disk and it’s recommended to perform power cycle on the drive to check for this issue.
Moreover, you can also check the SMART Status of My Book Live if you able to access the dashboard. This will provide the health details of My Book Live and would be helpful to check for the issue.

Thanks for your reply. I will check it out. At the moment I have a flashing white light that’s been flashing for days. The drive is not connected to anything other than a power source.