using System;

public class Program

{

public static void Main()

{

System.Globalization.CultureInfo provider = System.Globalization.CultureInfo.InvariantCulture;

// ********Choose the actual start time *********:

DateTime originalStartTime = DateTime.Now;

//DateTime originalStartTime = new DateTime(2012, 12, 25, 16, 30, 50);

// *********Choose the alert duration *********:

double minutes = 20;

Console.WriteLine ("Start Time of Alert: " + originalStartTime);

Console.WriteLine ("End Time of Alert: " + originalStartTime.AddMinutes(minutes));

Console.WriteLine ("Interval in minutes: " + minutes);

Console.WriteLine ("\n");

// Calculate the gap from 1/1/1900 to originalTime.

DateTime ntpEpoch = new DateTime(1900, 1, 1);

TimeSpan timeSince1900 = originalStartTime - ntpEpoch;

// Now add that time span to 1/1/0001 to get the time in the desired format.

DateTime dtEpoch = new DateTime(0001, 1, 1);

DateTime startNtpTime = dtEpoch + timeSince1900;

Console.WriteLine ("alertStartTime: " + startNtpTime);

    Console.WriteLine ("alertExpiryTime: " + startNtpTime.AddMinutes(minutes));

}

}

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