Ubuntu Server 20.04 running TightVNCServer > Main Menu in MATE desktop keeps closing by itself when clicked on from VNCViewer client

I am running Ubuntu Server 20.04 on a Raspberry Pi 4. I installed TightVNCServer so I could access the MATE desktop from VNCViewer on a Windows 7 laptop. The Pi 4 is overclocked to 2Ghz and has 4GB RAM. Ubuntu is very responsive and is working fine when accessed with a keyboard/mouse attached to the Pi 4.

I start the vncserver like this:

vncserver -geometry 1920x1080 :2

This matches my laptop screen resolution and the MATE desktop appears and sized correctly in the VNC Viewer on the win 7 laptop screen. However when I click on the MATE main Menu, to open it, it closes by itself after about a second so I can't use any programs.

Other menus on the desktop work fine, like the shutdown "cogwheel" and the Wifi/Network menu etc..

Here is my xstartup file:

#!/bin/sh

xrdb $HOME/.Xresources
xsetroot -solid grey
#x-terminal-emulator -geometry 80x24+10+10 -ls -title "$VNCDESKTOP Desktop" &
x-window-manager &
# Fix to make GNOME work
export XKL_XMODMAP_DISABLE=1
/etc/X11/Xsession
mate-session &

Is there some thing wrong with my setup?

I find the ubuntu desktop is a bit slow as well when navigated around using vncviewer and Youtube videos are unwatchable the playback is very jumpy... The Win 7 laptop running the VNC client on the connects to the LAN by wifi which may be a factor?

Another thing... when I installed TightVncServer I got the message:

Warning: ubuntu:1 is taken because of /tmp/.X11-unix/X1
Remove this file if there is no X server ubuntu:1
xauth:  file /root/.Xauthority does not exist

New 'X' desktop is ubuntu:2

I'm not sure if this means that there was a vncserver already installed on my Ubuntu server 20.04?

Update I installed the xfce and cinnamon desktops and I don't have this problem with either of them.

Can anyone see something wrong with my setup? Maybe it's with MATE... I didn't add any new themes or icons.

Solution 1:

do not running it as root, i ran it as default user, it works for me