Problem with firefox running on fluxbox/debian

[snowsurfa7]

Okay so I want to get firefox to run through fluxbox via VNC, however firefox wont start through fluxbox, nor through terminal, when I try and start it in terminal it says
(firefox-bin:7020): Gtk-WARNING **: cannot open display:
could anyone help me please? Thanks in advance!

[unknown_error]

check the permissions given on firefox!

is fluxbox running under the same user, you start firefox with?

is there any more output than:
(firefox-bin:7020): Gtk-WARNING **: cannot open display:

??

grz