Device Offline - This device is inaccessible

My Cloud OS 3 Personal & Network Attached Storage My Cloud
2

You are not providing a lot of information to work with.

First did you set the My Cloud up using an Apple computer?

Have you checked the dashboard to make sure cloud access is on and set up?

WDMCRemoteAccess.JPG


Taking a look in the User Manual and reading it should help you out a lot.
http://www.wdc.com/wdproducts/library/UM/ENG/4779-705103.pdf