Question: I have Ubuntu-Gnome 14.04 (Gnome 3.12.2).

When I try to run `gnome-terminal` by following command :

```
$ gnome-terminal
Error constructing proxy for org.gnome.Terminal: /org/gnome/Terminal/Factory0: 
Error calling StartServiceByName for org.gnome.Terminal:
GDBus.Error:org.freedesktop.DBus.Error.Spawn.ChildExited: 
Process /usr/lib/gnome-terminal/gnome-terminal-server exited with status 8

```

Answer: 
This might be an issue with your locales. Either add `LANG=en_US.UTF-8` to `/etc/locale.conf` and reboot or delete that file altogether (`sudo rm /etc/locale.conf && sudo locale-gen en_US.UTF-8 && sudo dpkg-reconfigure locales`) and reboot.
I had this problem when I created a new Ubuntu 16.04.3 LTS Desktop. The fix was to edit the `/etc/default/locale` file by adding the following line to the end of the file:

```
LC_ALL="en_US.UTF-8"

```

Then reboot and the problem was gone.