java.lang.NullPointerException at org.netbeans.core.HtmlBrowserComponent.componentActivated(HtmlBrowserComponent.java:159) Caused: java.lang.IllegalStateException: [Winsys] TopComponent org.netbeans.core.HtmlBrowserComponent throws runtime exception from its componentActivated() method. Please repair it! Probable cause is at org.netbeans.core.HtmlBrowserComponent.componentActivated(HtmlBrowserComponent.java:159) at org.openide.windows.WindowManager.logThrowable(WindowManager.java:363) at org.openide.windows.WindowManager.activateComponent(WindowManager.java:286) at org.netbeans.core.windows.WindowManagerImpl.notifyRegistryTopComponentActivated(WindowManagerImpl.java:1029) at org.netbeans.core.windows.Central.addModeClosedTopComponent(Central.java:858) at org.netbeans.core.windows.ModeImpl.addClosedTopComponent(ModeImpl.java:323) at org.netbeans.core.windows.ModeImpl.close(ModeImpl.java:238) at org.netbeans.core.windows.WindowManagerImpl.topComponentClose(WindowManagerImpl.java:1168) at org.openide.windows.TopComponent.close(TopComponent.java:498) at org.openide.windows.TopComponent.close(TopComponent.java:485) at org.netbeans.spi.palette.PaletteSwitch.showHidePaletteTopComponent(PaletteSwitch.java:263) at org.netbeans.spi.palette.PaletteSwitch.run(PaletteSwitch.java:145) at org.netbeans.spi.palette.PaletteSwitch$1.propertyChange(PaletteSwitch.java:320) at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339) at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:276) at org.netbeans.core.windows.RegistryImpl.doFirePropertyChange(RegistryImpl.java:316) at org.netbeans.core.windows.RegistryImpl.tryFireChanges(RegistryImpl.java:289) at org.netbeans.core.windows.RegistryImpl.selectedNodesChanged(RegistryImpl.java:234) at org.netbeans.core.windows.RegistryImpl.topComponentActivated(RegistryImpl.java:172) at org.netbeans.core.windows.WindowManagerImpl.notifyRegistryTopComponentActivated(WindowManagerImpl.java:1024) at org.netbeans.core.windows.Central.activateModeTopComponent(Central.java:1758) at org.netbeans.core.windows.WindowManagerImpl.topComponentRequestActive(WindowManagerImpl.java:1180) at org.openide.windows.TopComponent.requestActive(TopComponent.java:789) at org.netbeans.core.NbTopManager$NbBrowser.showUrl(NbTopManager.java:646) at org.netbeans.core.NbTopManager$NbBrowser.access$100(NbTopManager.java:587) at org.netbeans.core.NbTopManager$NbURLDisplayer$1.run(NbTopManager.java:234) at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209) at java.awt.EventQueue.dispatchEvent(EventQueue.java:633) at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:117) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:296) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:211) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:201) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:196) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:188) at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)