java.lang.IllegalArgumentException: view is invalid at javax.help.search.MergingSearchEngine.merge(MergingSearchEngine.java:91) at javax.help.JHelpSearchNavigator.merge(JHelpSearchNavigator.java:168) at javax.help.plaf.basic.BasicSearchNavigatorUI.addSubHelpSets(BasicSearchNavigatorUI.java:275) at javax.help.plaf.basic.BasicSearchNavigatorUI.reloadData(BasicSearchNavigatorUI.java:225) at javax.help.plaf.basic.BasicSearchNavigatorUI.installUI(BasicSearchNavigatorUI.java:174) at javax.swing.JComponent.setUI(JComponent.java:664) at javax.help.JHelpNavigator.setUI(JHelpNavigator.java:257) at javax.help.JHelpNavigator.updateUI(JHelpNavigator.java:276) at javax.help.JHelpNavigator.(JHelpNavigator.java:105) at javax.help.JHelpSearchNavigator.(JHelpSearchNavigator.java:66) at javax.help.SearchView.createNavigator(SearchView.java:80) at javax.help.JHelp.setupNavigators(JHelp.java:148) at javax.help.JHelp.(JHelp.java:126) at javax.help.JHelp.(JHelp.java:76) at org.netbeans.modules.javahelp.JavaHelp.createJHelp(JavaHelp.java:953) at org.netbeans.modules.javahelp.JavaHelp.createAndDisplayJHelp(JavaHelp.java:508) at org.netbeans.modules.javahelp.JavaHelp.showHelp(JavaHelp.java:487) at org.netbeans.modules.javahelp.HelpCtxProcessor$ShortcutAction.actionPerformed(HelpCtxProcessor.java:173) at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018) at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341) at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402) at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259) at javax.swing.AbstractButton.doClick(AbstractButton.java:376) at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:833) at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:877) at java.awt.Component.processMouseEvent(Component.java:6505) at javax.swing.JComponent.processMouseEvent(JComponent.java:3320) at java.awt.Component.processEvent(Component.java:6270) at java.awt.Container.processEvent(Container.java:2229) at java.awt.Component.dispatchEventImpl(Component.java:4861) at java.awt.Container.dispatchEventImpl(Container.java:2287) at java.awt.Component.dispatchEvent(Component.java:4687) at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4832) at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:4492) at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:4422) at java.awt.Container.dispatchEventImpl(Container.java:2273) at java.awt.Window.dispatchEventImpl(Window.java:2719) at java.awt.Component.dispatchEvent(Component.java:4687) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:735) at java.awt.EventQueue.access$200(EventQueue.java:103) at java.awt.EventQueue$3.run(EventQueue.java:694) at java.awt.EventQueue$3.run(EventQueue.java:692) at java.security.AccessController.doPrivileged(AccessController.java:0) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87) at java.awt.EventQueue$4.run(EventQueue.java:708) at java.awt.EventQueue$4.run(EventQueue.java:706) at java.security.AccessController.doPrivileged(AccessController.java:0) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.awt.EventQueue.dispatchEvent(EventQueue.java:705) at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:159) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138) at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)