I have installed Fedora 18 with Gnome desktop and installed tigervnc-server. This same setup has worked fine with several other computers with Fedora 17, allowing me to do remote connections with TightVNC Viewer from a Windows machine. However with Fedora 18 I get an "Oh no. Something has gone wrong" message in the VNC Client when I try to connect. If I force Gnome to fallback mode then the remote session works fine. Fedora 17 uses Gnome 3.4.2 and Fedora 18 uses Gnome 3.6.2 so that may have something to do with it. The remote session also works with KDE desktop but not LXDE or XFCE.
I have not found any posts from others about this situation so I expect that I am missing something obvious. If someone has an idea or can point me to the posting regarding this that I missed it would be great.