java.lang.NullPointerException
        at org.netbeans.core.windows.RegistryImpl.getActivated(RegistryImpl.java:99)
        at org.netbeans.core.windows.actions.UndockWindowAction.getTC2WorkWith(UndockWindowAction.java:133)
        at org.netbeans.core.windows.actions.UndockWindowAction.updateName(UndockWindowAction.java:122)
        at org.netbeans.core.windows.actions.UndockWindowAction.isEnabled(UndockWindowAction.java:117)
        at org.openide.awt.Actions$MenuBridge.updateState(Actions.java:952)
        at org.openide.awt.Actions$MenuItem.synchMenuPresenters(Actions.java:1302)
        at org.openide.awt.DynaMenuModel.checkSubmenu(DynaMenuModel.java:182)
        at org.openide.awt.MenuBar$LazyMenu.stateChanged(MenuBar.java:537)
        at javax.swing.DefaultButtonModel.fireStateChanged(DefaultButtonModel.java:333)
        at javax.swing.DefaultButtonModel.setRollover(DefaultButtonModel.java:266)
        at com.sun.java.swing.plaf.windows.WindowsMenuUI$WindowsMouseInputHandler.mouseEntered(WindowsMenuUI.java:241)
        at java.awt.Component.processMouseEvent(Component.java:6050)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3265)
        at java.awt.Component.processEvent(Component.java:5806)
        at java.awt.Container.processEvent(Container.java:2058)
        at java.awt.Component.dispatchEventImpl(Component.java:4413)
        at java.awt.Container.dispatchEventImpl(Container.java:2116)
        at java.awt.Component.dispatchEvent(Component.java:4243)
        at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4322)
        at java.awt.LightweightDispatcher.trackMouseEnterExit(LightweightDispatcher.java:4111)
        at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:3968)
        at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:3916)
        at java.awt.Container.dispatchEventImpl(Container.java:2102)
        at java.awt.Window.dispatchEventImpl(Window.java:2440)
        at java.awt.Component.dispatchEvent(Component.java:4243)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:104)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)