problem with ubuntu 12.10 on VirtualBox 4.2.8

[SLC]

Hello Sirs,
This morning. I installed Virtual box 4.2.6 and upgraded it to 4.2.8. on the OS Windows 7 64 bits host. After, I installed as guest Unbutu using the iso file : ubuntu-12.10-desktop-i386: I went through all the instaltion process with no problems.
Just at the end i got a message about compiz met an error and failled.
In consequence, when i try to launch ubuntu, I can access the login window but after to be logged: my desktop is emplty !
I mean: I only have the well known unbuntu background but no tool bar or and no icons. I can just move my mouse and that's all.
I try to open a command window (Ctrl+F2) with no effect.
Did you already meet this problem?
I searched on inetrnet for a solution. I found some solution to similar problem but I should use the command line w, hat I can't do it
I removed ubuntu and re-install it, with no effect.

regards
SLC

[Perryg]

First make sure that 3D acceleration in the guest settings is disabled.
Start the guest and see if you can actually get to the desktop. If so install the Guest additions (you probably will need to remove the ones Ubuntu installs first).

Hint I always install dkms build-essential linux-headers-generic first.

This should help Howto: Install Linux Guest Additions

[SLC]

Thanks for your quick answer.
I checked the guest's setting and the 3D acceleration was disabled. I was totaly confuse. Just for test purpose, I set the 3D accelaration and start unbuntu.
And it works the desktop is completed with the bar tool and the icons. I launched the terminal and install dkms build-essential linux-headers- generic.
But before to install the GA, I checked if 3D acceleration was set typing > /usr/bin/nux/unity_support_test -p
the result was : unity 3D supported yes !

I can tell you I am lost. I did not understand what happened but it seems it works. isn't it?

[Perryg]

You do need 3D because of unity but it should fallback to software rendering if you turn it off, at least that is the way Ubuntu is supposed to do it.
You can see if you are running the VBox OpenGL drivers by running the following in a terminal.
glxinfo | grep OpenGL
It should say chromium. If not then you are using software rendering and the CPU will be worked a lot harder.

Note: you may need to install a package (mesa-utils) to be able to use glxinfo

[SLC]

I type the command glxinfo
i got warning messages adn at the end the following :

OpenGL vendor string: Humper
OpenGL renderer string: chromium
OpenGL version string: 2.1 Chromium 1.9
OpenGL shading language version string: 3.30 - Intel build 8.15.10.2725
OpenGL extensions:

is it correct?

Thanks for your support

[Perryg]

Yes