Unable to export Task Sequence with dependencies in SCCM 2012 R2 SP1

System.NullReferenceException

Object reference not set to an instance of an object.

Stack Trace:

at Microsoft.ConfigurationManagement.Migration.ObjectSerialization.Modeling.PrototypeImpl.TryGetPropertyValue(Object instance, String propertyName, Object& value)

at Microsoft.ConfigurationManagement.Migration.ObjectSerialization.Modeling.EntityHandle.TryGetValue[T](String propName, T& value)

at Microsoft.ConfigurationManagement.AdminConsole.MigrationAssistant.ExportPageControl.relatedWoker_DoWork(Object sender, DoWorkEventArgs e)

at System.ComponentModel.BackgroundWorker.OnDoWork(DoWorkEventArgs e)

at System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument)

Remove the checkmark “Use an unattended or Sysprep answer file…” from Apply OS step, the export goes fine.

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