Telerik RadDatePicker Donna Data dzisiaj WPF
Ok I have solved the problem. The binding DataType to the column is DateTime, which don't accept null values. Null values is what the GridView produces upon clicking add new row. When such thing happens, DateTime will auto return 01/01/0001, which is then passed to the RadDatePicker. The solution is to change the datatype to Nullable DateTime, which is 'DataType?'.
Obedient Ostrich