diff --git a/plugins/UM3NetworkPrinting/DiscoverUM3Action.qml b/plugins/UM3NetworkPrinting/DiscoverUM3Action.qml
index b1964c6c06..b9b85ef2d4 100644
--- a/plugins/UM3NetworkPrinting/DiscoverUM3Action.qml
+++ b/plugins/UM3NetworkPrinting/DiscoverUM3Action.qml
@@ -279,7 +279,7 @@ Cura.MachineAction
                     wrapMode: Text.WordWrap
                     text:{
                         // The property cluster size does not exist for older UM3 devices.
-                        if(base.selectedPrinter.clusterSize == null || base.selectedPrinter.clusterSize == 1)
+                        if(base.selectedPrinter != undefined && base.selectedPrinter.clusterSize == null || base.selectedPrinter.clusterSize == 1)
                         {
                             return "";
                         }