using (var adapter = DataAdapter(ref em, isHistory, _connection, _transaction))
                {
                    if (_connection.State == ConnectionState.Closed)
                        _connection.Open();
                    
                     adapter.Update(dtExcel);

                    //Некоторый код

                  
                    _transaction.Commit();
                }

            }
            catch (Exception ex)
            {

                 //Некоторый код
              
              _transaction.Rollback();
            }

using (var adapter = DataAdapter(ref em, isHistory, _connection, _transaction))
                {
                    adapter.RowUpdated += adapter_RowUpdated;

                    if (_connection.State == ConnectionState.Closed)
                        _connection.Open();
                    
                     adapter.Update(dtExcel);

                    adapter.RowUpdated -= adapter_RowUpdated;

                    //Некоторый код

                  
                    _transaction.Commit();
                }

            }
            catch (Exception ex)
            {

                 //Некоторый код
              
              _transaction.Rollback();
            }


//Добавленный обработчик событие RowUpdated
        private void adapter_RowUpdated(object sender, SqlRowUpdatedEventArgs e)
        {
            var row = e.Row;

            if (e.Errors != null)
                e.Errors =
                    new Exception(e.Errors.Message + " в строке номер " + (row.Table.Rows.IndexOf(row) + 1) + " справочника.");
        }