Remove guest login or disable guest login in Ubuntu

When you start up the Ubuntu desktop, you notice that it shows the Guest login. To prevent this from appearing on the login screen, do the following:

1. Start up the terminal on your system
2. Backup the /etc/lightdm/lightdm.conf file for Ubuntu versions 13.10 and below:
   $ sudo cp /etc/lightdm/lightdm.conf /etc/lightdm/lightdm.conf.org <enter>
3. Backup the /etc/lightdm/lightdm.conf.d/10-xubuntu.conf file.
4. Modify the file to add a line “allow-guest=false” as below for Ubuntu versions 13.10 and below
   $ sudo gedit /etc/lightdm/lightdm.conf <enter>
   Add a line to the end of the file:
   allow-guest=false
5. Backup the /etc/lightdm/lightdm.conf.d/10-xubuntu.conf file for Ubuntu versions 14.04 onwards:
   $ sudo cp /etc/lightdm/lightdm.conf.d/10-xubuntu.conf /etc/lightdm/lightdm.conf.d/10-xubuntu.conf.org <enter>
6. Modify the above file and add the line shown in green text as in 4 above to this file.
7. Save the file.

The next time you start your computer, you will not find the Guest login on the login screen.