GUI and blank VNC desktop

I used this document

https://www.linode.com/docs/application … untu-12-04">https://www.linode.com/docs/applications/remote-desktop/using-vnc-to-operate-a-desktop-on-ubuntu-12-04

to setup a gui on my linode.

However, when I bring up VNCviewer I get a blank desktop? The desktop is grey and has a moving X mouse, with a VNC menu at the top of the page, but the desktop is blank?

Any input would be apprciated. -