diff --git a/scripts/Muon/GUI/Common/grouping_table_widget/grouping_table_widget_presenter.py b/scripts/Muon/GUI/Common/grouping_table_widget/grouping_table_widget_presenter.py
index 34c8a969ad8c8256e8cff35f47e2933530b18a91..f3212e7b4d1a5af19595fc68b7d7def09760ea26 100644
--- a/scripts/Muon/GUI/Common/grouping_table_widget/grouping_table_widget_presenter.py
+++ b/scripts/Muon/GUI/Common/grouping_table_widget/grouping_table_widget_presenter.py
@@ -50,7 +50,8 @@ class GroupingTablePresenter(object):
         return True
 
     def validate_detector_ids(self, text):
-        if re.match(run_utils.run_string_regex, text):
+        # detector_list = run_utils.run_string_to_list(text)
+        if re.match(run_utils.run_string_regex, text) and max(run_utils.run_string_to_list(text)) <= self._model._data.num_detectors:
             return True
         self._view.warning_popup("Invalid detector list.")
         return False
@@ -119,6 +120,7 @@ class GroupingTablePresenter(object):
             try:
                 self.update_model_from_view()
             except ValueError as error:
+                self._model.remove_pairs_with_removed_name(self._view.get_table_item_text(row, 0))
                 self._view.warning_popup(error)
 
         self.update_view_from_model()
diff --git a/scripts/Muon/GUI/Common/utilities/load_utils.py b/scripts/Muon/GUI/Common/utilities/load_utils.py
index c2f704d73893c4cf99a26fc2eb8a023d4b2812b0..ba6d267437d1df44f9165a97d1c6f810707ea5c0 100644
--- a/scripts/Muon/GUI/Common/utilities/load_utils.py
+++ b/scripts/Muon/GUI/Common/utilities/load_utils.py
@@ -149,7 +149,7 @@ DEFAULT_OUTPUTS = ["OutputWorkspace",
                    "FirstGoodData",
                    "MainFieldDirection"]
 # List of default values for the DEFAULT_OUTPUTS list
-DEFAULT_OUTPUT_VALUES = [__default_workspace(),
+DEFAULT_OUTPUT_VALUES = [[__default_workspace()],
                          None,  # api.WorkspaceFactoryImpl.Instance().createTable("TableWorkspace"),
                          api.WorkspaceFactoryImpl.Instance().createTable("TableWorkspace"),
                          0.0,