Also, go into the Geometries folder and find the muscular Mike .obj file. (I don't have the mesh, so I don't know the exact name nor where it is stored in the geometries folder.) In the folder that has the .obj file, you'll also find a .rsr file with the same name. Delete the .rsr file. It is a copy of the .obj that Poser uses. Sometimes that gets corrupted. It could be causing the problem.