When I try to use X11 forwarding, I am getting the error, "cannot open display" message.
If I use trusted X11 forwarding "-Y", then it works as expected. I can use x2go without any issues. My ssh_config and sshd_config both permit X11 Forwarding (both on remote server and on local client).
Additionally, I even allowed X access from all clients via xhost +. When remoting into my box (without -Y), I see the DISPLAY env variable is unset. When remoting into my box (with -Y), I see the DISPLAY env variable is set. If I merely try to set the DISPLAY env variable (even when not using -Y), that has no effect.
I believe I should not be using trusted X11 forwarding as there is a slight security risk by doing so (even though it works).