Full Factory Reset

My Cloud OS 3 Personal & Network Attached Storage My Cloud
21

I take it you read p84 of the user manual, that describes the three types of reset pretty clearly?

And says this:

  1. In the System Factory Restore section, click the desired type of restore: System
    Only, Quick Restore or Full Restore.
  2. When asked to confirm the action, click Yes.
  3. When the progress bar displays, if you selected Full Restore in step 1, but you change
    your mind, click Switch to Quick to start a Quick Restore from the beginning.

So you can abort a Full Restore and switch to a Quick Restore if you get bored waiting.