diff --git a/cura/PrintInformation.py b/cura/PrintInformation.py
index cdb558b77c..ab63e4034d 100644
--- a/cura/PrintInformation.py
+++ b/cura/PrintInformation.py
@@ -185,7 +185,7 @@ class PrintInformation(QObject):
         if self._active_material_container:
             try:
                 self._active_material_container.metaDataChanged.disconnect(self._onMaterialMetaDataChanged)
-            except TypeError:
+            except TypeError: #pyQtSignal gives a TypeError when disconnecting from something that is already disconnected.
                 pass
 
         active_material_id = Application.getInstance().getMachineManager().activeMaterialId
diff --git a/cura/Settings/MachineManager.py b/cura/Settings/MachineManager.py
index e01c16849a..f94bffc643 100755
--- a/cura/Settings/MachineManager.py
+++ b/cura/Settings/MachineManager.py
@@ -236,9 +236,15 @@ class MachineManager(QObject):
         if self._global_container_stack:
             try:
                 self._global_container_stack.nameChanged.disconnect(self._onMachineNameChanged)
+            except TypeError: #pyQtSignal gives a TypeError when disconnecting from something that was already disconnected.
+                pass
+            try:
                 self._global_container_stack.containersChanged.disconnect(self._onInstanceContainersChanged)
+            except TypeError:
+                pass
+            try:
                 self._global_container_stack.propertyChanged.disconnect(self._onPropertyChanged)
-            except:
+            except TypeError:
                 pass
             material = self._global_container_stack.material
             material.nameChanged.disconnect(self._onMaterialNameChanged)