Xwindow error

[brouwers roland lx]

Hello Everyone,

I installed a program linneighborhood
when I launch it in a sh 
I get 
-----------------------------------
Gtk-WARNING **: cannot open display: cath.cat.be:6.0
[root at cath bin]# xhost +
Xlib: connection to "cath.cat.be:6.0" refused by server
Xlib: No protocol specified

xhost:  unable to open display "cath.cat.be:6.0"
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It is not because of linNeighborhood, I have this very often.

How can I fixe this?

Roland
roland at cat.be