diff --git a/src/calibre/gui2/__init__.py b/src/calibre/gui2/__init__.py
index 8f275ec065..da254a7b3f 100644
--- a/src/calibre/gui2/__init__.py
+++ b/src/calibre/gui2/__init__.py
@@ -328,6 +328,19 @@ def info_dialog(parent, title, msg, det_msg='', show=False,
         return d.exec_()
     return d
 
+def show_restart_warning(msg, parent=None):
+    d = warning_dialog(parent, _('Restart needed'), msg,
+            show_copy_button=False)
+    b = d.bb.addButton(_('Restart calibre now'), d.bb.AcceptRole)
+    b.setIcon(QIcon(I('lt.png')))
+    d.do_restart = False
+    def rf():
+        d.do_restart = True
+    b.clicked.connect(rf)
+    d.set_details('')
+    d.exec_()
+    b.clicked.disconnect()
+    return d.do_restart
 
 
 class Dispatcher(QObject):
diff --git a/src/calibre/gui2/device.py b/src/calibre/gui2/device.py
index 8c74c3db9c..6d638ef9c2 100644
--- a/src/calibre/gui2/device.py
+++ b/src/calibre/gui2/device.py
@@ -19,7 +19,8 @@ from calibre.gui2.dialogs.choose_format_device import ChooseFormatDeviceDialog
 from calibre.utils.ipc.job import BaseJob
 from calibre.devices.scanner import DeviceScanner
 from calibre.gui2 import (config, error_dialog, Dispatcher, dynamic,
-        warning_dialog, info_dialog, choose_dir, FunctionDispatcher)
+        warning_dialog, info_dialog, choose_dir, FunctionDispatcher,
+        show_restart_warning)
 from calibre.ebooks.metadata import authors_to_string
 from calibre import preferred_encoding, prints, force_unicode, as_unicode
 from calibre.utils.filenames import ascii_filename
@@ -895,10 +896,10 @@ class DeviceMixin(object): # {{{
         d.accept = validate
         if d.exec_() == d.Accepted:
             dev.save_settings(cw)
-            warning_dialog(self, _('Disconnect device'),
-                    _('Disconnect and re-connect the %s for your changes to'
-                        ' be applied.')%dev.get_gui_name(), show=True,
-                    show_copy_button=False)
+            do_restart = show_restart_warning(_('Restart calibre for the changes to %s'
+                ' to be applied.')%dev.get_gui_name(), parent=self)
+            if do_restart:
+                self.quit(restart=True)
 
     def _sync_action_triggered(self, *args):
         m = getattr(self, '_sync_menu', None)
diff --git a/src/calibre/gui2/preferences/main.py b/src/calibre/gui2/preferences/main.py
index 4c879c7883..8af41c805a 100644
--- a/src/calibre/gui2/preferences/main.py
+++ b/src/calibre/gui2/preferences/main.py
@@ -9,14 +9,14 @@ import textwrap
 from functools import partial
 from collections import OrderedDict
 
-from PyQt4.Qt import QMainWindow, Qt, QIcon, QStatusBar, QFont, QWidget, \
-        QScrollArea, QStackedWidget, QVBoxLayout, QLabel, QFrame, QKeySequence, \
-        QToolBar, QSize, pyqtSignal, QPixmap, QToolButton, QAction, \
-        QDialogButtonBox, QHBoxLayout
+from PyQt4.Qt import (QMainWindow, Qt, QIcon, QStatusBar, QFont, QWidget,
+        QScrollArea, QStackedWidget, QVBoxLayout, QLabel, QFrame, QKeySequence,
+        QToolBar, QSize, pyqtSignal, QPixmap, QToolButton, QAction,
+        QDialogButtonBox, QHBoxLayout)
 
 from calibre.constants import __appname__, __version__, islinux
-from calibre.gui2 import gprefs, min_available_height, available_width, \
-    warning_dialog
+from calibre.gui2 import (gprefs, min_available_height, available_width,
+    show_restart_warning)
 from calibre.gui2.preferences import init_gui, AbortCommit, get_plugin
 from calibre.customize.ui import preferences_plugins
 
@@ -346,19 +346,8 @@ class Preferences(QMainWindow):
                         'restarted immediately. You will not be allowed to '
                         'set any more preferences, until you restart.')
 
+            do_restart = show_restart_warning(msg, parent=self)
 
-            d = warning_dialog(self, _('Restart needed'), msg,
-                    show_copy_button=False)
-            b = d.bb.addButton(_('Restart calibre now'), d.bb.AcceptRole)
-            b.setIcon(QIcon(I('lt.png')))
-            d.do_restart = False
-            def rf():
-                d.do_restart = True
-            b.clicked.connect(rf)
-            d.set_details('')
-            d.exec_()
-            b.clicked.disconnect()
-            do_restart = d.do_restart
         self.showing_widget.refresh_gui(self.gui)
         self.hide_plugin()
         if self.close_after_initial or (must_restart and rc) or do_restart: