Xfce No option to quit X on session manager

[bugzeo]

I've installed xfce4, and now it automatically loads the login screen. However I want to run again desktop-installer but says me "server is already active for display 0", and CTRL+ALT+BACKSPACE does not kill X server. how can I quit it and change from XDM to SLiM?

Here's the screenshot with no X kill option:

 

[bugzeo]

After running again desktop-installer with option 2 says "/usr/local/sbin/desktop-installer: auto-update-xorg.conf: not found"

 

[CuatroTorres]

As root:

ee /etc/ttys #ttyv8 on -> off
pkg install slim
sysrc slim_enable=YES

Chapter 3. FreeBSD Basics

Basic commands and functionality of the FreeBSD operating system

docs.freebsd.org

 

[bugzeo]

Thanks, worked. Now I have another problem:
XFCE4 does not launch on FreeBSD Virtualbox guest

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