Can you provide the code excerpt.
This error is not in the Zentity “original” source code.
This might not be helpful I guess, but here is a correct use of Observable collection tolist
ObservableCollection<string> obs =
new ObservableCollection<string>();
obs.Add("a");
obs.Add("b");
obs.Add("c");
obs.Add("d");
List<string> ls = obs.ToList<string>();
If you can provide me the code excerpt or tell me what you are wanting to do will help me to provide a useful answer.
-Regards