java.lang.AssertionError: OperationSupport cannot be null because OperationContainer contains elements: [] and invalid elements [] at org.netbeans.modules.autoupdate.ui.wizards.InstallStep.handleDownload(InstallStep.java:189) at org.netbeans.modules.autoupdate.ui.wizards.InstallStep.doDownloadAndVerificationAndInstall(InstallStep.java:167) at org.netbeans.modules.autoupdate.ui.wizards.InstallStep.access$200(InstallStep.java:91) at org.netbeans.modules.autoupdate.ui.wizards.InstallStep$2.run(InstallStep.java:159) at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:561) at org.openide.util.RequestProcessor$Processor.doEvaluate(RequestProcessor.java:1031) at org.openide.util.RequestProcessor$Task.waitFinished(RequestProcessor.java:723) at org.netbeans.modules.autoupdate.ui.wizards.InstallStep$1.propertyChange(InstallStep.java:143) at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:333) at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:270) at java.awt.Component.firePropertyChange(Component.java:7277) at org.netbeans.modules.autoupdate.ui.wizards.OperationPanel.access$000(OperationPanel.java:61) at org.netbeans.modules.autoupdate.ui.wizards.OperationPanel$1.run(OperationPanel.java:81) at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:561) at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:986)