Olá, Boa Tarde.

Estava com o fonte do meu sistema aberto, depois de um certo tempo o Netbeans 
não mostrou mais o fonte....dando o seguinte erro no log:

ERROR: Cannot initialize guarded sections... code generation is disabled.
*********** Exception occurred ************ at 3:32 PM on May 25, 2007
java.lang.NullPointerException
	at javax.swing.text.JTextComponent.setDocument(JTextComponent.java:410)
	at org.openide.text.QuietEditorPane.setDocument
(QuietEditorPane.java:102)
	at org.openide.text.CloneableEditor.initialize
(CloneableEditor.java:211)
	at org.openide.text.CloneableEditor.getEditorPane
(CloneableEditor.java:629)
	at 
org.netbeans.core.multiview.MultiViewCloneableTopComponent.getEditorPane
(MultiViewCloneableTopComponent.java:225)
	at org.openide.text.CloneableEditorSupport.getOpenedPanes
(CloneableEditorSupport.java:850)
	at 
org.netbeans.modules.debugger.projects.EditorContextImpl.getCurrentEditor
(EditorContextImpl.java:575)
	at 
org.netbeans.modules.debugger.projects.EditorContextImpl.getCurrentLineNumber
(EditorContextImpl.java:235)
	at 
org.netbeans.modules.debugger.projects.RunToCursorActionProvider.shouldBeEnable
d(RunToCursorActionProvider.java:143)
	at 
org.netbeans.modules.debugger.projects.RunToCursorActionProvider.access$100
(RunToCursorActionProvider.java:58)
	at 
org.netbeans.modules.debugger.projects.RunToCursorActionProvider$Listener.prope
rtyChange(RunToCursorActionProvider.java:190)
	at java.beans.PropertyChangeSupport.firePropertyChange
(PropertyChangeSupport.java:333)
	at java.beans.PropertyChangeSupport.firePropertyChange
(PropertyChangeSupport.java:270)
	at org.netbeans.core.windows.RegistryImpl.doFirePropertyChange
(RegistryImpl.java:249)
	at org.netbeans.core.windows.RegistryImpl.tryFireChanges
(RegistryImpl.java:222)
	at org.netbeans.core.windows.RegistryImpl.selectedNodesChanged
(RegistryImpl.java:186)
	at org.netbeans.core.windows.RegistryImpl.topComponentActivated
(RegistryImpl.java:138)
	at 
org.netbeans.core.windows.WindowManagerImpl.notifyRegistryTopComponentActivated
(WindowManagerImpl.java:913)
	at org.netbeans.core.windows.Central.setActiveMode(Central.java:182)
	at org.netbeans.core.windows.WindowManagerImpl.setActiveMode
(WindowManagerImpl.java:611)
	at org.netbeans.core.windows.PersistenceHandler.load
(PersistenceHandler.java:178)
	at org.netbeans.core.windows.WindowSystemImpl.load
(WindowSystemImpl.java:39)
	at org.netbeans.core.NonGui$3.run(NonGui.java:218)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:461)
[catch] at java.awt.EventDispatchThread.pumpOneEventForHierarchy
(EventDispatchThread.java:242)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy
(EventDispatchThread.java:163)
	at java.awt.EventDispatchThread.pumpEvents
(EventDispatchThread.java:157)
	at java.awt.EventDispatchThread.pumpEvents
(EventDispatchThread.java:149)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)