public void AbsoluteDayYearTooLow() { DateTime calendar = new DateTime(1899, 1, 1); try { HSSFDateUtil.AbsoluteDay(calendar, false); Assert.Fail("Should fail here"); } catch (ArgumentException e) { // expected here } try { calendar = new DateTime(1903, 1, 1); HSSFDateUtil.AbsoluteDay(calendar, true); Assert.Fail("Should fail here"); } catch (ArgumentException e) { // expected here } }