SkyBox shows boxiness. why?

I have this skybox I made and the colors along the edges don't match up (I know thats a problem, and I know how to fix it).

The real problem I'm having is there is a line down the edges of the sky box. how could this be and why? you can see it in the picture. photobucket is down so I had to use another service. you'll have to download the picture in order to view it.

I can't view your image. However I think what you mean is those visible seams revealing the boxiness of the skybox. If that's the case you need make the wrap mode for all your images to clamp. I think the default is on repeat.