Managed to connect to my server using thinlinc client but icons are missing :(

That’s a new one to me.

Are you able to look at the .desktop file for each one of those, and make sure the filepath for the icon actually exists?

The icons are displayed when I login locally, rather than from Windows.

amonra@charon:~$ cat Desktop/computer.desktop
[Desktop Entry]
Type=Application
Exec=pcmanfm-qt computer:///
Icon=computer
Name=Computer
amonra@charon:~$

Icons:

amonra@charon:~$ find /usr/share/icons -name computer.svg
/usr/share/icons/Adwaita/scalable/devices/computer.svg
/usr/share/icons/HighContrast/scalable/devices/computer.svg
/usr/share/icons/Humanity/devices/16/computer.svg
/usr/share/icons/Humanity/devices/22/computer.svg
/usr/share/icons/Humanity/devices/24/computer.svg
/usr/share/icons/Humanity/devices/48/computer.svg
/usr/share/icons/Humanity/devices/64/computer.svg
/usr/share/icons/LoginIcons/apps/64/computer.svg
/usr/share/icons/Papirus-Dark/16x16/devices/computer.svg
/usr/share/icons/Papirus/16x16/devices/computer.svg
/usr/share/icons/Papirus/22x22/devices/computer.svg
/usr/share/icons/Papirus/24x24/devices/computer.svg
/usr/share/icons/Papirus/32x32/devices/computer.svg
/usr/share/icons/Papirus/48x48/devices/computer.svg
/usr/share/icons/Papirus/64x64/devices/computer.svg
/usr/share/icons/ePapirus/16x16/devices/computer.svg
/usr/share/icons/ePapirus-Dark/16x16/devices/computer.svg
amonra@charon:~$ find /usr/share/icons -name computer.png
/usr/share/icons/HighContrast/16x16/devices/computer.png
/usr/share/icons/HighContrast/22x22/devices/computer.png
/usr/share/icons/HighContrast/24x24/devices/computer.png
/usr/share/icons/HighContrast/256x256/devices/computer.png
/usr/share/icons/HighContrast/32x32/devices/computer.png
/usr/share/icons/HighContrast/48x48/devices/computer.png
/usr/share/icons/gnome/16x16/devices/computer.png
/usr/share/icons/gnome/22x22/devices/computer.png
/usr/share/icons/gnome/24x24/devices/computer.png
/usr/share/icons/gnome/256x256/devices/computer.png
/usr/share/icons/gnome/32x32/devices/computer.png
/usr/share/icons/gnome/48x48/devices/computer.png
/usr/share/icons/oxygen/base/128x128/devices/computer.png
/usr/share/icons/oxygen/base/16x16/devices/computer.png
/usr/share/icons/oxygen/base/22x22/devices/computer.png
/usr/share/icons/oxygen/base/256x256/devices/computer.png
/usr/share/icons/oxygen/base/32x32/devices/computer.png
/usr/share/icons/oxygen/base/48x48/devices/computer.png
/usr/share/icons/oxygen/base/64x64/devices/computer.png
/usr/share/icons/elementary-xfce/devices/128/computer.png
/usr/share/icons/elementary-xfce/devices/16/computer.png
/usr/share/icons/elementary-xfce/devices/22/computer.png
/usr/share/icons/elementary-xfce/devices/24/computer.png
/usr/share/icons/elementary-xfce/devices/32/computer.png
/usr/share/icons/elementary-xfce/devices/48/computer.png
/usr/share/icons/elementary-xfce/devices/64/computer.png
amonra@charon:~$

As for which one is being used I don’t know