My current Problem is, that when I try to install Ubuntu 12.04 Desktop, neither unity nor gnome are installed. During the installation, I am prompted with the message that only the core is installed, and which additional packages I would like to have installed. When I select ubuntu-desktop, the installer grabs some packages and installs them, but after completing the installation and booting into my Ubuntu, i dont get any GUI, but instead I have the command line interface.

When I try to start a new Unity session, i get an error saying that Unity is not installed, so I tried to install it. However this changes nothing, my PC still boots into the Command Line.

Are there any solutions to my problem? Any help would be greatly appreciated. Thanks in advance.

EDIT: I tried to fix it with the following commands:

$ sudo apt-get install ubuntu-desktop
$ sudo apt-get install gdm
$ sudo /etc/init.d/gdm start

When I try to boot, I get the Ubuntu splash screen, but then the screen mainly shows white squares, with a few black ones at the top.