How to transform our own fxb files to c3b?

I used 3ds max 2015 to export a simple fxb file which only contains a cube without any textures.
But I got an error when using the fbx-conv to transform the fxb file to c3b:
ERROR: FBX SDK encountered an error: Unknown.
Could anyone tell me how to transform the file correctly?
Thank you.

I have solved this problem by use a new version fbx-conv tool by IvIong
site: fbx-conv tool
I think the tool will be updated in the next cocos2dx version.

Remember the fbx file should include a material so the tool would transform successfully.