Gnome not found !

unable to launch "gnome-session --session=cairo-dock" X session --- "gnome-session --session=cairo-dock" not found; falling back to default session.
this message appears when i try to choose cairo gnome instead of kde plasma workspace , how to solve it ?

What do you want to do exactly ? Running gnome desktop instead of kde plasma ?
Then you need to install gnome and gnome-session. In your case you also need cairo-dock for this session to work.

SO you mean Gnome is supported in Netrunner but not preinstalled ?

Yes exactly