Because actual Pluging only install virtualBox 4.x that have problems to connect to Win10 using RDP, and VirtualBox 5.0.2 works fine.
My suggest is to create a new Virtualbox 5.0 Pluging to avoid problems described here: Some help please - virtualbox won't update to latest version
I actually install 4.3 pluging, and once stoped execute vb5.shell script that suggest subzero, but a new plugging is easyer for beginers.