diff --git a/DiscoverUM3Action.py b/DiscoverUM3Action.py
index 4ca500dc48..7115822582 100644
--- a/DiscoverUM3Action.py
+++ b/DiscoverUM3Action.py
@@ -23,8 +23,12 @@ class DiscoverUM3Action(MachineAction):
             self._network_plugin.addPrinterSignal.connect(self._onPrinterDiscoveryChanged)
             self._network_plugin.removePrinterSignal.connect(self._onPrinterDiscoveryChanged)
             self.printersChanged.emit()
+
+    @pyqtSlot()
+    def restartDiscovery(self):
+        if not self._network_plugin:
+            self.startDiscovery()
         else:
-            # Restart bonjour discovery
             self._network_plugin.startDiscovery()
 
     def _onPrinterDiscoveryChanged(self, *args):
diff --git a/DiscoverUM3Action.qml b/DiscoverUM3Action.qml
index 4dcb5e074d..dcfd76792b 100644
--- a/DiscoverUM3Action.qml
+++ b/DiscoverUM3Action.qml
@@ -70,7 +70,7 @@ Cura.MachineAction
         {
             id: rediscoverButton
             text: catalog.i18nc("@title", "Refresh")
-            onClicked: manager.startDiscovery()
+            onClicked: manager.restartDiscovery()
             anchors.right: parent.right
             anchors.rightMargin: parent.width * 0.5
         }