diff --git a/io_import_scene_mhx.py b/io_import_scene_mhx.py
index d0eb5a58587b91924c340a732e4b1374f011384b..79065155ff0f29524adc09627d4828196c71ce6a 100644
--- a/io_import_scene_mhx.py
+++ b/io_import_scene_mhx.py
@@ -4542,7 +4542,8 @@ class VIEW3D_OT_MhxDisableAllLayersButton(bpy.types.Operator):
                     break
         else:
             layers[0] = True
-        rig.data.layers = layers            
+        if rig:
+            rig.data.layers = layers
         return{'FINISHED'}    
                 
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