Hi Hugo,

Hugo M <ham1988@gmail.com> writes:

> I'm using 24.3.50.1 with Xubuntu.

What version of Org are you using?

M-x org-version RET

Chances are that you use Org <8.0, in which case we can only recommend
to upgarde: http://orgmode.org/manual/Installation.html

HTH,

--
 Bastien