virtualbox.org

Do you have 3D enabled for that VM, and if so does disabling it make a difference? Might this be the same thing as in topic 52215[1]? Yes. It looks the same issue. I am using Ubuntu 10.04.4 with compiz 3d effect. So I disabled the 3D Acc. and the desktop work. But Ubuntu 12.04.1 with Unity desktop ...

I upgrade VBoxGuestAdditions 4.2.0 to 4.2.2 of Ubuntu 10.04.4. After restart the VM and login, the Gnome desktop enviroment never show. I force restart it and login as Gnome SafeMode the desktop come back. Then I logout and select Gnome as nomal, the desktop went away again. But Ubuntu 12.04.1 runs ...

When the preferences is opened and it told me invalid setting detected.
I didn't check enable proxy but Host&Port field still ask me to complete it.
It's VBox 4.2.2.