Gtk-WARNING **: cannot open display:

[Niels Larsen <niel@telia.com>]

I am using debian sarge.

When I try to run: "sudo synaptic" I get the below warning.

(synaptic:4338): Gtk-WARNING **: cannot open display:

I have to my ~/.bash_profile file added following, according to advice from 
some mailing list, but it does not help:

if [[ -z $DISPLAY ]]; then
	export DISPLAY=:0.0
fi

And I ran: "sources ~/.bash_profile" right after

Any suggestions?

Thanks in advance  :-)

I am a newbie, so please do explain a little bit in detail, as I find linux 
enormous with commands, and possibly do give a small example *smile*
Not only what to do, but also how to do  *humour - smile*
Many times I find examples better than "long" explanations?