Can't make change to Group "[Type Name]" with more than one instance. To resolve: Ungroup and Group again under a new name. Edit and make change, then change all instances of the original Group to the new Group. 
   Namespace:   Autodesk.Revit.DB  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
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