diff --git a/Demo/tkinter/guido/electrons.py b/Demo/tkinter/guido/electrons.py
index d764380..f16c3fa 100755
--- a/Demo/tkinter/guido/electrons.py
+++ b/Demo/tkinter/guido/electrons.py
@@ -55,8 +55,11 @@
 		try:
 			while 1:
 				self.random_move(self.n)
-		finally:
-			self.tk.destroy()
+		except TclError:
+			try:
+				self.tk.destroy()
+			except TclError:
+				pass
 
 
 # Main program