Why do I need a password to view public share

Hello dinkybluebug, currently there is no supported option to setup a password for the Public folder. You can create password protected shares for the users you create from the My Book Live Dashboard, but this should have no effect on the Public folder. From where are you trying to access the Public folder? If you are trying to access it from a Windows PC, check the link below for the steps to use the WD Discovery tool. 

How to install WD Discovery on Windows