**System Information**
windows 7, amd radeon 5570
**Blender Version**
2.74
**Short description of error**
**Exact steps for others to reproduce the error**
Rendered an animation with -b, at the end it gave me
Exception ignored in: <bound method CyclesRender.__del__ of <bpy_struct, CyclesRender invalid>>
Traceback (most recent call last):
File "C:\Program Files\Blender Foundation\Blender\2.74\scripts\addons\cycles\__init__.py", line 49, in __del__ engine.free(self)
File "C:\Program Files\Blender Foundation\Blender\2.74\scripts\addons\cycles\engine.py", line 49, in free if hasattr(engine, "session"):
ReferenceError: StructRNA of type CyclesRender has been removed
Blender quit