Unity is gone. All window buttons gone. how to fix it?

Question

Today I logged in ubuntu and without me doing any changes to the system recently, unity is gone. I have no dash, i can't move around my windows. What I noticed is that e.g nautilus opens but there are no window frames/buttons. I found a relative question in the forums, tried the answer but nothing changed. Can someone help me fix or re-install unity? Thanks in advance

Answer 1

Try this:

    sudo apt-get update
    sudo apt-get install --reinstall ubuntu-desktop
    sudo apt-get install unity