添加Outlook日历项时无法设置开始和结束时间

我用它来添加一个日历条目到一个共享日历(它不会将它添加到共享日历),它也不会设置开始和结束时间,它只是将条目添加为一个全天事件。这可能吗,我一直在用这个:

private void AddAppointment()
{
    try
    {
        var AppOutlook = new Outlook.Application();
        Outlook.AppointmentItem newAppointment = (Outlook.AppointmentItem)AppOutlook.CreateItem(Outlook.OlItemType.olAppointmentItem);
        Microsoft.Office.Interop.Outlook.NameSpace oNS = AppOutlook.GetNamespace("MAPI");
        Microsoft.Office.Interop.Outlook.Recipient oRep = null;               
        oRep = oNS.CreateRecipient("Someone Elses Calendar");                
        newAppointment.Start = DateTime.Now.AddHours(3);
        newAppointment.End = DateTime.Now.AddHours(4);
        newAppointment.Location = "remote";
        newAppointment.Body = "Test Calendar Entry";
        newAppointment.BusyStatus = Outlook.OlBusyStatus.olTentative;
        newAppointment.AllDayEvent = true;
        newAppointment.Subject = "Test Calendar Entry";
        newAppointment.Save();
        newAppointment.Display(true);
    }
    catch (Exception ex)
    {
        MessageBox.Show("The following error occurred: " + ex.Message);
    }
}