Sharepoint / Data Access Page / Missing images

I have created a Data Access Page that looks great when viewed from my PC.

I then load the page onto Sharepoint and it works great except for one issue:

The navigation buttons and the background image show up as broken images (x-box image/graphic).

Does anyone know what’s causing this and more importantly, how to fix it?

The data and functionality is fine. The navigation buttons still work. They just don’t look pretty.
Thanks.