More info: Unpacking xfce4-session (4.10.1-3ubuntu5) ...dpkg: error processing archive /var/cache/apt/archives/xfce4-session_4.10.1-3ubuntu5_i386.deb (--unpack): trying to overwrite '/etc/xdg/autostart/xscreensaver.desktop', which is also in package trisquel-desktop-common-data 7.0-15
This looks more relevant.
