diff --git a/ProcessGCodeJob.py b/ProcessGCodeJob.py
index 195fc87747..b9f9a9f2be 100644
--- a/ProcessGCodeJob.py
+++ b/ProcessGCodeJob.py
@@ -19,7 +19,11 @@ class ProcessGCodeJob(Job):
                 objectIdMap[id(node)] = node
 
         if self._message.id in objectIdMap:
-            node = objectIdMap[self._message.id]
+            try:
+                node = objectIdMap[self._message.id]
+            except KeyError:
+                return
+
             with open(self._message.filename) as f:
                 data = f.read(None)
                 setattr(node.getMeshData(), 'gcode', data)
diff --git a/ProcessSlicedObjectListJob.py b/ProcessSlicedObjectListJob.py
index 7cb5fa6760..8ca7b0fde4 100644
--- a/ProcessSlicedObjectListJob.py
+++ b/ProcessSlicedObjectListJob.py
@@ -25,7 +25,12 @@ class ProcessSlicedObjectListJob(Job):
         layerHeight = Application.getInstance().getActiveMachine().getSettingValueByKey('layer_height')
 
         for object in self._message.objects:
-            mesh = objectIdMap[object.id].getMeshData()
+            try:
+                node = objectIdMap[object.id]
+            except KeyError:
+                continue
+
+            mesh = node.getMeshData()
 
             layerData = LayerData.LayerData()
             for layer in object.layers: