diff --git a/novelwriter/gui/projtree.py b/novelwriter/gui/projtree.py
index 5faa85b2..96af1ecd 100644
--- a/novelwriter/gui/projtree.py
+++ b/novelwriter/gui/projtree.py
@@ -1693,19 +1693,23 @@ class GuiProjectTree(QTreeWidget):
                 del self._treeMap[tHandle]
                 return None
 
-        else:
+        elif pHandle in self._treeMap:
             byIndex = -1
             if nHandle is not None and nHandle in self._treeMap:
-                try:
-                    byIndex = self._treeMap[pHandle].indexOfChild(self._treeMap[nHandle])
-                except Exception:
-                    logger.error("Failed to get index of item with handle '%s'", nHandle)
+                byIndex = self._treeMap[pHandle].indexOfChild(self._treeMap[nHandle])
             if byIndex >= 0:
                 self._treeMap[pHandle].insertChild(byIndex + 1, newItem)
             else:
                 self._treeMap[pHandle].addChild(newItem)
             self.propagateCount(tHandle, nwItem.wordCount, countChildren=True)
 
+        else:
+            self.mainGui.makeAlert(self.tr(
+                "There is nowhere to add item with name '{0}'."
+            ).format(nwItem.itemName), nwAlert.ERROR)
+            del self._treeMap[tHandle]
+            return None
+
         self.setTreeItemValues(tHandle)
         newItem.setExpanded(nwItem.isExpanded)
 
diff --git a/tests/test_gui/test_gui_projtree.py b/tests/test_gui/test_gui_projtree.py
index cbf607d8..684f4dd3 100644
--- a/tests/test_gui/test_gui_projtree.py
+++ b/tests/test_gui/test_gui_projtree.py
@@ -885,6 +885,11 @@ def testGuiProjTree_Other(qtbot, monkeypatch, nwGUI, projPath, mockRnd):
     nwGUI.theProject.tree[nHandle].setParent(None)
     assert projTree.revealNewTreeItem(nHandle) is False
 
+    # Try to add an item with unknown parent to the tree
+    nHandle = nwGUI.theProject.newFile("Test", C.hNovelRoot)
+    nwGUI.theProject.tree[nHandle].setParent(C.hInvalid)
+    assert projTree.revealNewTreeItem(nHandle) is False
+
     # Method: undoLastMove
     # ====================