java.util.ConcurrentModificationException
        at java.util.HashMap$HashIterator.nextEntry(HashMap.java:793)
        at java.util.HashMap$EntryIterator.next(HashMap.java:834)
        at java.util.HashMap$EntryIterator.next(HashMap.java:832)
        at org.netbeans.core.startup.NbInstaller.shouldDelegateClasspathResource(NbInstaller.java:842)
        at org.netbeans.ModuleManager$SystemClassLoader.shouldDelegateResource(ModuleManager.java:470)
        at org.netbeans.ProxyClassLoader.loadClass(ProxyClassLoader.java:207)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
        at org.openide.loaders.InstanceSupport.findClass(InstanceSupport.java:493)
Caused: java.lang.ClassNotFoundException: From file: MultiFileObject@17c748f[Menu/Profile/org-netbeans-modules-prof-actions-LoadSnapshotAction.instance] due to: java.util.ConcurrentModificationException
        at org.openide.loaders.InstanceSupport.instanceClass(InstanceSupport.java:159)
        at org.openide.loaders.InstanceDataObject$Ser.instanceClass(InstanceDataObject.java:1228)
        at org.openide.loaders.InstanceDataObject.instanceClass(InstanceDataObject.java:738)
        at org.openide.awt.MenuBar$LazyMenu$MenuFolder.acceptCookie(MenuBar.java:637)
        at org.openide.loaders.FolderInstance.acceptDataObject(FolderInstance.java:420)
        at org.openide.loaders.FolderInstance.defaultProcessObjects(FolderInstance.java:767)
        at org.openide.loaders.FolderInstance.access$000(FolderInstance.java:101)
        at org.openide.loaders.FolderInstance$1R.init(FolderInstance.java:685)
        at org.openide.loaders.FolderInstance$1R.run(FolderInstance.java:712)
        at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:573)
        at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1005)