Remove Guest Login Option on Ubuntu 14.04 & 16.04 LTS
Post date: May 09, 2014 3:56:28 PM
Just press Ctrl+Alt+T on your keyboard to open Terminal.
When it opens, run these commands:
sudo pico /usr/share/lightdm/lightdm.conf.d/50-ubuntu.conf
Add this line, save and close.
allow-guest=false
Reboot your PC, and the guest option will be gone.