I was having the same problem as bc90021, and the solution in the thread linked to by Ms. Phitt didn't work.
GreenN00b's suggestion worked, but I didn't need to take the step of opening a root shell:
...at this point vino-server began spitting out messages to the command line. I used Vinagre as usual from the local machine to connect. When my VNC session was done, I typed Ctrl+C in the ssh session to return me to a prompt, and then:
user@local:~$ ssh remote
user@remote:~$ DISPLAY=:0.0 /usr/lib/vino/vino-server&
To go back to bc90021's comments:
user@remote:~$ kill -HUP 9211
+ Hangup /usr/lib/vino/vino-server
Agreed, this is bad. See LP#292994.
1) This is not easy.
2) There is no documentation for this process.
3) There is no man page for vino-server.
There is a reason for this. As far as I can tell, vino allows access only to an active session of the user who starts it. If albert wants to allow remote access, but bill doesn't, they establish this by enabling/disabling vino individually. If albert isn't logged in, no instance of vino-service runs for him; this saves resources.
4) Vino-server is not a service that can be stopped and started in /etc/init.d.
There are instructions elsewhere about how to set up VNC servers that will give you the GDM login screen when you connect, and allow you to log in as any user. However, these don't give you the option to connect to an existing GNOME session. I would like to see this integrated with the desktop; currently it takes some work to set up.
Turns out not
5) I might be required to reboot the machine in order to fix this issue.