title: tfpt unshelve migrate showing "An item with the same key has already been added."
body: <p>I am follwing the example here <a href="https://stackoverflow.com/questions/3728318/branch-from-local-workspace">Branch from local workspace</a> because I have the same scenario.</p>
  
  <p>Shelveset details dialog appear, after clicking unshelve it showing "An item with the same key has already been added."</p>
  
  <p>Any advice please?</p>