Error Circular Reference in Texture Stack

I’m trying to bake this textured model, but this error pops up
Circular reference in texture stack.> texture
Here is the template for can bake: Model in .obj

Circular reference error means that texture used as source for baking is also chosen as target for baking.
Since no more details regarding render engine or texture baking type are included it’s too hard to tell exactly what is baking to what but the process is everywhere the same. You select resource for baking (in case of normals it will be details of highpoly, in case of albedo baking it would be texture / nodes used for coloring the mesh etc.), then choose target of baking (if in Cycles, unconnected texture in the node editor not used anywhere else; if in Internal, texture assigned in UV editor to faces of the mesh and not assigned to any other mesh).
Note that if object has multiple materials you have to check all of them (this especially for Cycles) or bake on a copy of an object which has all materials but one removed.