diff --git a/tryton/gui/window/board.py b/tryton/gui/window/board.py
index 25604a08dd..a6b7458fa0 100644
--- a/tryton/gui/window/board.py
+++ b/tryton/gui/window/board.py
@@ -44,8 +44,12 @@ class Board(SignalEvent):
 
         self.handlers = {
             'but_reload': self.sig_reload,
+            'but_close': self.sig_close,
         }
 
     def sig_reload(self, test_modified=True):
         self.board.reload()
         return True
+
+    def sig_close(self):
+        return True
diff --git a/tryton/gui/window/tree.py b/tryton/gui/window/tree.py
index 2f8fba0b47..8681d9ee0b 100644
--- a/tryton/gui/window/tree.py
+++ b/tryton/gui/window/tree.py
@@ -89,6 +89,7 @@ class Tree(SignalEvent):
             'but_action': self.sig_action,
             'but_print': self.sig_print,
             'but_save_as': self.sig_save_as,
+            'but_close': self.sig_close,
         }
         signals = {
             'on_but_sc_go_clicked': self.sc_go,
@@ -316,3 +317,6 @@ class Tree(SignalEvent):
                 self.tree_res.fields, [], parent=self.window,
                 context=self.context)
         win.run()
+
+    def sig_close(self):
+        return True