Possible Duplicate:
Unity doesn't load, no Launcher, no Dash appears
I recently upgraded Ubuntu from version 11.04 to 11.10. After about two days of using this new version the Dash didn't appear on the top, and I wasn't able to access the programs that I use. Let me describe:
The bar on the top with the clock and Internet connections is not there. The only remains are the notification messages that a connection has been found, which allows me to connect to the Internet; and the menus from what appear to be a nautilus application but I'm not sure, they read File Edit View Go Bookmarks Help, and they open my Home Folder.
The icons of my favourite applications are not there, and I am unable to access them wit Alt+F2 or the Super key. The only thing that's available is the Terminal with the shortcut Ctrl+Alt+T.
By the way, in order to keep using the computer I had to run the Ubuntu 2D version at the beginning, but as you would imagine that is not optimal since I was already looking forward to the new features of Ubuntu 11.10.