both API's contain the type

http://thebuildingcoder.typepad.com/blog/2014/01/calculating-a-rolling-offset-between-two-pipes.html @jeremytammik BuildingSystemsDBAPI and CurtainGridFamilyDBAPI.dll both contain the FamilySymbol type error despite qualified naming: Autodesk.Revit.DB.FamilySymbol symbol = new Autodesk.Revit.DB.FilteredElementCollector(doc) .OfClass(typeof(Autodesk.Revit.DB.FamilySymbol)) .OfCategory(BuiltInCategory.OST_PipeFitting) .Cast\< Autodesk.Revit.DB.FamilySymbol \>() .Where\(e => e.Family.Name.Contains("Elbow - Generic")) .FirstOrDefault\(); slashes added for the forum