What version of Windows client are you using?

[Michael] :  version 3.99.0.4

What is KFCE? If you selected "GNOME" in the client, how can it know to start KFCE?

[Michael] I hadn’t thought about that. I thought it knew from your login profile which DE you used.

Did you mean XFCE?

[Michael] Sorry, XFCE yes

I still use the 3.01-13 client, since all the newer ones have various problems. But even with those problems, I can still connect with the newer versions. I just tested 3.99.0.4, and I could connect (but it still have problems, most notably it freezes when trying to play most youtube videos).

Anyway, I use XFCE, and I choose "Custom" in the client, and give it the command "/usr/bin/startxfce4" and it gives me almost the same startup messages as you posted, but it does connect and allow me to use the desktop normally (except all the clients have a bug where it sets the Windows window size too small when you choose a custom resolution, say 800x600, the windows client sets the outer dimensions of the window to 800x600 but of course the windows title bar takes up 25-30 pixels, so the window ends up being too small to display an 800x600 desktop).

[Michael] Tried that, no change

I wonder why the client does not have XFCE as an option.

[Michael] That would be nice