When I make the normal map or the cavity map, I get the error "Circular reference in texture stack". I did not get it yesterday, but at some point I realized I did things wrong and had to start over again. So, I did start over again and then it keeps giving me this error whenever I want to bake my normal and cavity map. My base and AO map work fine....
I'm pretty sure the solution is to remove your material, then bake.