Connection errors when switching render layers

[Solution1]
fixRenderLayerOutAdjustmentErrors;

If you are using Maya 2010:

1. make sure all your references are loaded
   

2.in the Maya MEL command input line, enter fixRenderLayerOutAdjustmentErrors;

If you are using Maya 2009 (or previous):

1.download the scripts FixRenderLayerOutAdjustmentErrors.mel and
FixRenderLayerOutAdjustmentErrors.res.mel

2.copy them to your maya/2009/scripts directory (read more here),
so they will source automatically when you next load Maya.

3.make sure all your references are loaded

4.in the Maya MEL command input line, enter fixRenderLayerOutAdjustmentErrors;

The script is provided with the installation of Maya 2010, so you don't need to download it. View the release notes for Maya 2010.

fixRenderLayerOutAdjustmentErrors;

[원문] http://mayastation.typepad.com/maya-station/2009/12/connection-errors-when-switching-render-layers.html