diff --git a/actor/src/actor_client.py b/actor/src/actor_client.py
index 722dba7c..d285f7f9 100755
--- a/actor/src/actor_client.py
+++ b/actor/src/actor_client.py
@@ -69,7 +69,7 @@ if __name__ == "__main__":
     timer.start(1000)
     timer.timeout.connect(lambda *a: None)  # timeout can be connected to a callable
 
-    qApp.exec_()
+    qApp.exec()
 
     # On windows, if no window is created, this point will never be reached.
     qApp.end()
diff --git a/actor/src/actor_config.py b/actor/src/actor_config.py
index d580e888..bc90205b 100755
--- a/actor/src/actor_config.py
+++ b/actor/src/actor_config.py
@@ -192,4 +192,4 @@ if __name__ == "__main__":
 
     myapp = UDSConfigDialog()
     myapp.show()
-    sys.exit(app.exec_())
+    sys.exit(app.exec())
diff --git a/actor/src/actor_config_unmanaged.py b/actor/src/actor_config_unmanaged.py
index 03076b6b..d11abcfa 100755
--- a/actor/src/actor_config_unmanaged.py
+++ b/actor/src/actor_config_unmanaged.py
@@ -62,7 +62,7 @@ class UDSConfigDialog(QDialog):
         self.ui.host.setText(self._config.host)
         self.ui.validateCertificate.setCurrentIndex(1 if self._config.validateCertificate else 0)
         self.ui.logLevelComboBox.setCurrentIndex(self._config.log_level)
-        self.ui.serviceToken.setText(self._config.master_token)
+        self.ui.serviceToken.setText(self._config.master_token or '')
 
         self.ui.testButton.setEnabled(bool(self._config.master_token and self._config.host))
 
@@ -153,4 +153,4 @@ if __name__ == "__main__":
 
     myapp = UDSConfigDialog()
     myapp.show()
-    sys.exit(app.exec_())
+    sys.exit(app.exec())