diff --git a/gui/wxpython/mapswipe/frame.py b/gui/wxpython/mapswipe/frame.py
index 9165a3ac319..36bcf5b6d3f 100644
--- a/gui/wxpython/mapswipe/frame.py
+++ b/gui/wxpython/mapswipe/frame.py
@@ -754,7 +754,8 @@ def OnCloseWindow(self, event):
         self.GetFirstMap().Clean()
         self.GetSecondMap().Clean()
         self._mgr.UnInit()
-        self._inputDialog.UnInit()
+        if self._inputDialog:
+            self._inputDialog.UnInit()
         self.Destroy()