@wei2912: simply running Display=":0.0" will not work. You need to run the following command from a virtual console, exactly as it's written (same capitalisation, and so on): DISPLAY=":0.0" gnome-shell
@wei2912: simply running Display=":0.0" will not work. You need to run the following command from a virtual console, exactly as it's written (same capitalisation, and so on):
DISPLAY=":0.0" gnome-shell