Xorg dummy driver

[quizhead]

Hi,
I tried to install a headless dummy driver on an instance which I can connect only via RDP and configured it like so:

Section “Device”
Identifier “Configured Video Device”
Driver “dummy”
VideoRam 16384
EndSection
Section “Monitor”
Identifier “Configured Monitor”
HorizSync 31.5-48.5
VertRefresh 50-70
EndSection
Section “Screen”
Identifier “Default Screen”
Monitor “Configured Monitor”
Device “Configured Video Device”
DefaultDepth 24
SubSection “Display”
Depth 24
Modes “3440×1440”
EndSubSection
EndSection

After that the Desktop option disappeared.
Where did I go wrong?
Thanks.