Install

Install MateDesktop VNC and xrdp
apt-get install ubuntu-mate-core ubuntu-mate-desktop -y
apt-get install tightvncserver -y
apt-get install xrdp -y
Setting xrdp
echo mate-session >~/.xsession

vim /etc/xrdp/startwm.sh
# insert mate-session before ./etc/X11/Xsession`

reboot

Uninstall

apt-get purge xrdp
apt-get purge tightvncserver