// Error: file: C:/Program Files/Autodesk/Maya2018/scripts/startup/layerEditor.mel line 3146: Cannot switch from ‘CH’ to ‘defaultRenderLayer’ because of an override to a missing node within a referenced scene. Reload the referenced scene if it’s unloaded, clean up the referenced scene or remove corresponding reference edits if the node has been deleted in the referenced scene
    打开文件，切换渲染层时会报这个错误，而且无法切换渲染层；上谷歌搜了一圈，发现maya有自带的修复渲染层的mel命令：
    fixRenderLayerOutAdjustmentErrors
    运行后就恢复正常了