Brighten 3D portal

Hi Guys,
i buit a tank in blender. the 3D portal is very dark.
even though I have tried everything regarding lamps, it wont brighten the portal.
Is there a way I can make the world brighter?
cheers.
Ian

The portals in the area lamp is to help brighten indoor scenes, by telling Blender where windows are and where light should go more. A screenshot of what you are doing would help.

When i booed up this AM, it seemed to have fixed itself.
thanks for the reply