While booting, encountered the following exception
which hung NetBeans:

java.lang.IllegalStateException: Duplicate pair in
treePair1: <broken:
Services/Hidden/org-netbeans-modules-web-core-resources-EntityCatalog.xml>
pair2:
SL[/Hidden/org-netbeans-modules-web-core-resources-EntityCatalog
index1: -1 index2: -1 item1: null item2:
org.netbeans.core.xml.EntityCatalogImpl@f711d0
id1: b29b4a id2: f15427
	at
org.openide.util.lookup.ALPairComparator.compare(ALPairComparator.java:52)
	at java.util.TreeMap.compare(TreeMap.java:1085)
	at java.util.TreeMap.put(TreeMap.java:463)
	at java.util.TreeSet.add(TreeSet.java:209)
	at
org.openide.util.lookup.AbstractLookup$R.initItems(AbstractLookup.java:788)
	at
org.openide.util.lookup.AbstractLookup$R.allItemsWithoutBeforeLookup(AbstractLookup.java:749)
	at
org.openide.util.lookup.AbstractLookup$R.allInstances(AbstractLookup.java:691)
	at
org.openide.util.lookup.ProxyLookup$R.computeResult(ProxyLookup.java:369)
	at
org.openide.util.lookup.ProxyLookup$R.allInstances(ProxyLookup.java:320)
	at
org.openide.util.lookup.ProxyLookup$R.computeResult(ProxyLookup.java:369)
	at
org.openide.util.lookup.ProxyLookup$R.allInstances(ProxyLookup.java:320)
	at
org.openide.xml.EntityCatalog$Forwarder.resolveEntity(EntityCatalog.java:82)
	at
org.apache.xerces.util.EntityResolverWrapper.resolveEntity(Unknown
Source)
	at
org.apache.xerces.impl.XMLEntityManager.resolveEntity(Unknown
Source)
	at
org.apache.xerces.impl.XMLDocumentScannerImpl$DTDDispatcher.dispatch(Unknown
Source)
	at
org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown
Source)
	at
org.apache.xerces.parsers.XML11Configuration.parse(Unknown
Source)
	at
org.apache.xerces.parsers.XML11Configuration.parse(Unknown
Source)
	at
org.apache.xerces.parsers.XMLParser.parse(Unknown
Source)
	at
org.apache.xerces.parsers.DOMParser.parse(Unknown
Source)
	at
org.apache.xerces.jaxp.DocumentBuilderImpl.parse(Unknown
Source)
	at org.openide.xml.XMLUtil.parse(XMLUtil.java:283)
	at
org.netbeans.modules.kjava.KJavaModule.add2Toolbar(KJavaModule.java:145)
	at
org.netbeans.modules.kjava.KJavaModule.initToolbars(KJavaModule.java:136)
	at
org.netbeans.modules.kjava.KJavaModule.restored(KJavaModule.java:74)
	at
org.netbeans.core.modules.NbInstaller.loadCode(NbInstaller.java:354)
	at
org.netbeans.core.modules.NbInstaller.load(NbInstaller.java:263)
	at
org.netbeans.core.modules.ModuleManager.enable(ModuleManager.java:861)
	at
org.netbeans.core.modules.ModuleList.installNew(ModuleList.java:552)
	at
org.netbeans.core.modules.ModuleList.trigger(ModuleList.java:487)
	at
org.netbeans.core.modules.ModuleSystem.scanForNewAndRestore(ModuleSystem.java:302)
	at org.netbeans.core.NonGui.run(NonGui.java:348)
	at org.netbeans.core.Main.run(Main.java:294)
	at
org.netbeans.core.NbTopManager.getNbTopManager(NbTopManager.java:233)
	at
org.netbeans.core.NbTopManager.get(NbTopManager.java:188)
	at org.netbeans.core.Main.start(Main.java:485)
	at
org.netbeans.core.TopThreadGroup.run(TopThreadGroup.java:90)
[catch] at java.lang.Thread.run(Thread.java:552)



At the same time, I also encountered the other
following exception:

Annotation: Exception occurred in Request Processor
java.lang.IllegalStateException: You cannot use
SL[/Hidden/Versioning Settings in more than one
AbstractLookup
	at
org.openide.util.lookup.AbstractLookup$Pair.setIndex(AbstractLookup.java:510)
	at
org.openide.util.lookup.InheritanceTree$Node.assignItem(InheritanceTree.java:938)
	at
org.openide.util.lookup.InheritanceTree.add(InheritanceTree.java:154)
	at
org.openide.util.lookup.DelegatingStorage.add(DelegatingStorage.java:75)
	at
org.openide.util.lookup.AbstractLookup.setPairsAndCollectListeners(AbstractLookup.java:224)
	at
org.openide.util.lookup.AbstractLookup.setPairs(AbstractLookup.java:203)
	at
org.openide.util.lookup.AbstractLookup$Content.setPairs(AbstractLookup.java:885)
	at
org.openide.loaders.FolderLookup$ProxyLkp.update(FolderLookup.java:336)
	at
org.openide.loaders.FolderLookup.createInstance(FolderLookup.java:170)
	at
org.openide.loaders.FolderInstance.defaultProcessObjects(FolderInstance.java:704)
	at
org.openide.loaders.FolderInstance.access$000(FolderInstance.java:68)
	at
org.openide.loaders.FolderInstance$2.run(FolderInstance.java:591)
	at
org.openide.loaders.FolderLookup.postCreationTask(FolderLookup.java:234)
	at
org.openide.loaders.FolderInstance.processObjects(FolderInstance.java:589)
	at
org.openide.loaders.FolderInstance$Listener.finished(FolderInstance.java:864)
	at
org.openide.loaders.FolderList.createObjects(FolderList.java:636)
	at
org.openide.loaders.FolderList.getObjects(FolderList.java:504)
	at
org.openide.loaders.FolderList.access$200(FolderList.java:50)
	at
org.openide.loaders.FolderList$ListTask.run(FolderList.java:869)
	at org.openide.util.Task.run(Task.java:136)
	at
org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:330)
[catch] at
org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:686)


Prior to this bootup, I had encountered previous
exceptions like the second one listed in the
process of changing projects. While the initial
boot failed, after killing the process and
attempting to start again, NetBeans loaded without
errors.