12.04 ubuntu-12.04-desktop-i386

忘了说了 是用虚拟机装的

不管怎么说 请你先登录吧

详细原因看我的博客：
http://hi.baidu.com/24688395/item/b9097897c98230845814618b
临时解决，看下面：
Follow the Steps ...
用自己创建的用户登录，然后接下来：
Restore the /etc/issue file:
sudo mv /etc/issue.backup /etc/issue
Restore the /etc/rc.local file:
sudo mv /etc/rc.local.backup /etc/rc.local
Restore the /etc/init/lightdm.conf file:
sudo mv /opt/vmware-tools-installer/lightdm.conf /etc/init
Thenreboot.