If that is the case, run either of these checks in a terminal to see the results:
/usr/lib/nux/unity_support_test -p
/usr/lib/nux/unity_support_test -p --compiz
/usr/lib/nux/unity_support_test -p --compiz
If you get this error message:
bash: /usr/lib/nux/unity_support_test: No such file or directory
see this troubleshooting guide:
http://www.tuxgarage.com/2011/04/missing-top-and-side-panels-in-unity.html
Those checks can be skipped if
- you have a blacklisted video card/chip,
- they are delivering incorrect results.
Add "UNITY_FORCE_START=1" to "/etc/environment":
gksudo gedit /etc/environment
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games"
UNITY_FORCE_START=1
UNITY_FORCE_START=1
Modify "/usr/share/gnome-session/sessions/classic-gnome.session":
sudo cp /usr/share/gnome-session/sessions/classic-gnome.session /usr/share/gnome-session/sessions/classic-gnome.session.bak
gksudo gedit /usr/share/gnome-session/sessions/classic-gnome.session
gksudo gedit /usr/share/gnome-session/sessions/classic-gnome.session
Remove the red marked entries:
[GNOME Session]
Name=Classic GNOME
Required=windowmanager;panel;filemanager;
Required-windowmanager=gnome-wm
Required-panel=gnome-panel
Required-filemanager=nautilus
DefaultApps=gnome-settings-daemon;
IsRunnableHelper=/usr/lib/nux/unity_support_test --compiz
FallbackSessionsID=GNOME2d
GNOME2d=2d-gnome
Name=Classic GNOME
Required=windowmanager;panel;filemanager;
Required-windowmanager=gnome-wm
Required-panel=gnome-panel
Required-filemanager=nautilus
DefaultApps=gnome-settings-daemon;
IsRunnableHelper=/usr/lib/nux/unity_support_test --compiz
FallbackSessionsID=GNOME2d
GNOME2d=2d-gnome