MDT Unhandled Exception: System.ArgumentException: An item with the same key has already been added

Question

After I have created a deploy task sequence in MDT, I get this exception when I try to edit the unattend.xml Full text of the exception is:

   Unhandled Exception: System.ArgumentException: An item with the same key has already been added.
   at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
   at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
   at System.Collections.ObjectModel.KeyedCollection`2.AddKey(TKey key, TItem item)
   at System.Collections.ObjectModel.KeyedCollection`2.InsertItem(Int32 index, TItem item)
   at Microsoft.ComponentStudio.ComponentPlatformInterface.WimInfo..ctor(String wimPath)
   at Microsoft.ComponentStudio.ComponentPlatformInterface.Cpi.OpenWim(String wimPath)
   at Microsoft.BDD.Catalog.Program.DoCatalog()
   at Microsoft.BDD.Catalog.Program.Main(String[] args)
Non-zero return code from catalog utility, rc = -532462766