You're not necessarily out of memory. This is one of Poser's standard error messages and means that the .rsr file associated with one of the .obj files in your scene has become corrupted. Find the obj files in the Runtime/geometries/foldername folder and delete the associated .rsr. Poser will rebuild it the next time you load the object.

Expert in computer code including, but not limited to, BTW; IIRC; IMHO; LMAO; BRB; OIC; ROFL; TTYL. Black belt in Google-fu.