Change public share access to read only for public and full access to selected users

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

There appears to be a bug in the Dashboard that you can exploit to turn off public access to Public, and enable individual user controls. See the end of this thread:

http://community.wd.com/t5/WD-My-Cloud/Guest-User-security-concerns-on-My-Cloud-2TB-Personal-Cloud/m-p/881649