Clement Lefebvre’s blog entry on how to upgrade Linux Mint to Version 18.2 (Sonya) indicates that the new LightDM display manager, along with the “Slick” greeter, is not installed by default. However, a section of the blog shows how to switch from MDM to LightDM.
Having updated my installation to Sonya, I decided to give LightDM a try. Essentially this involves using the command: apt install slick-greeter lightdm-settings. However, rebooting the computer produced the error message “Failed to start the X server”.
Ignoring this error resulted in the new login screen being displayed. The writeup on the Mint web site of Sonya’s new features asserted that the Slick greeter: “…provides the computer with a beautiful login screen…” Regrettably, in my view, the login screen isn’t particularly pretty. So, given this, and the evident need to troubleshoot the failure to start the Xserver, I decided to revert back to MDM.
This was easily done using the command:
sudo dpkg-reconfigure mdm
To clean things up, I also uninstalled LightDM using the command:
sudo apt-get purge lightdm
How to upgrade to Linux Mint 18.2
New features in Linux Mint 18.2 MATE
How To Install LightDM In Linux Mint (And Replace MDM)
How to uninstall lightdm?