Query time oledb c#

string connectionString = @"Provider=Microsoft.JET.OlEDB.4.0;" + @"Data Source=data.mdb";
                    using (var cnn = new OleDbConnection(connectionString))
                    {
                        string query = "Select * from sales where dateend >= @DateEnd";
                        string time = "5/31/2015 2:01:15 PM";
                        DataTable table = new DataTable();
                        OleDbCommand cmd = new OleDbCommand(query, cnn);
                        //if (para != null)
                        //    cmd.Parameters.AddRange(para);
                        //cmd.Parameters.AddWithValue("@DateEnd", DateTime.Now.ToString("MM/dd/yyyy h:mm:ss tt"));
                        cmd.Parameters.AddWithValue("@DateEnd", time);
                        cmd.CommandType = CommandType.Text;
                        cnn.Open();
                        table.Load(cmd.ExecuteReader());