set system time c# not working

I'm trying to set Windows SystemTime in a c# Application on Windows. I've implemented the example that is in every forum (including here) but it's not responding. I have a private class with two methods: GetSystemTime() and SetSystemTime(). GetSystemTime is working fine, but SetSystemTime is not setting the time I'm trying to pass from GetNetworkTime(). I'm doing something wrong? I've researched and I don't know if it's a privilege problem (I'm logged as Administrator, it shouldn't) or maybe a problem with date format.

The thing is: Should I see change in System clock when SetSystemTime() finishes? How I know it's running well? Because I'm not seeing any changes. Here I copy the class, and also GetNetworkTime Method, which get the actual hour from and NTP Server.

public static class SystemTime
    {
        [DllImport("kernel32.dll", SetLastError = true)]
        private extern static void GetSystemTime(ref SYSTEMTIME systime);
        [DllImport("kernel32.dll", SetLastError = true)]
        private extern static uint SetSystemTime(ref SYSTEMTIME systime);

        private struct SYSTEMTIME
        {
            public ushort wYear;
            public ushort wMonth;
            public ushort wDayOfWeek;
            public ushort wDay;
            public ushort wHour;
            public ushort wMinute;
            public ushort wSecond;
            public ushort wMilliseconds;
        }

        private static void GetTime()
        {
            // Call the native GetSystemTime method
            // with the defined structure.
            SYSTEMTIME stime = new SYSTEMTIME();
            GetSystemTime(ref stime);
        }

        public static void SetTime()
        {
            GetTime();
            SYSTEMTIME systime = new SYSTEMTIME();
            try
            {
                DateTime d = Intex.Core.Utils.Common.GetNetworkTime();

                systime.wHour = (ushort)d.Year;
                systime.wMonth = (ushort)d.Month;
                systime.wDayOfWeek = (ushort)d.DayOfWeek;
                systime.wDay = (ushort)d.Day;
                systime.wHour = (ushort)d.Hour;
                systime.wMinute = (ushort)d.Minute;
                systime.wSecond = (ushort)d.Second;
                systime.wMilliseconds = (ushort)d.Millisecond;

                SetSystemTime(ref systime);
                GetTime();
            }
            catch (Exception)
            {
                GetSystemTime(ref systime);
                SetSystemTime(ref systime);
           } 

        }
    }


public static DateTime GetNetworkTime()
    {
        //default Windows time server
        string ntpServer = ConfigurationManager.AppSettings["NTPServer"];

        // NTP message size - 16 bytes of the digest (RFC 2030)
        var ntpData = new byte[48];

        //Setting the Leap Indicator, Version Number and Mode values
        ntpData[0] = 0x1B; //LI = 0 (no warning), VN = 3 (IPv4 only), Mode = 3 (Client Mode)

        var addresses = Dns.GetHostEntry(ntpServer).AddressList;

        //The UDP port number assigned to NTP is 123
        var ipEndPoint = new IPEndPoint(addresses[0], 123);
        //NTP uses UDP
        var socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

        socket.Connect(ipEndPoint);

        //Stops code hang if NTP is blocked
        socket.ReceiveTimeout = 3000;

        socket.Send(ntpData);
        socket.Receive(ntpData);
        socket.Close();

        //Offset to get to the "Transmit Timestamp" field (time at which the reply 
        //departed the server for the client, in 64-bit timestamp format."
        const byte serverReplyTime = 40;

        //Get the seconds part
        ulong intPart = BitConverter.ToUInt32(ntpData, serverReplyTime);

        //Get the seconds fraction
        ulong fractPart = BitConverter.ToUInt32(ntpData, serverReplyTime + 4);

        //Convert From big-endian to little-endian
        intPart = SwapEndianness(intPart);
        fractPart = SwapEndianness(fractPart);

        var milliseconds = (intPart * 1000) + ((fractPart * 1000) / 0x100000000L);

        //**UTC** time
        var networkDateTime = (new DateTime(1900, 1, 1, 0, 0, 0, DateTimeKind.Utc)).AddMilliseconds((long)milliseconds);

        return networkDateTime.ToLocalTime();            
    }

    static uint SwapEndianness(ulong x)
    {
        return (uint)(((x & 0x000000ff) << 24) +
                       ((x & 0x0000ff00) << 8) +
                       ((x & 0x00ff0000) >> 8) +
                       ((x & 0xff000000) >> 24));
    }

The MSDN says

If the function succeeds, the return value is nonzero. If the function fails, the return value is zero. To get extended error information, call GetLastError.

See http://msdn.microsoft.com/en-us/library/windows/desktop/ms724942%28v=vs.85%29.aspx for whole page.

Did you try to check the return value and hence, last error ?

Here is a code sample to get return value and last error code : (just replace your own "SetSystemTime" call)

var ret = SetSystemTime(ref systime);
Console.WriteLine("SetSystemTime return : " + ret);
System.Console.WriteLine("Last error : " + GetLastError());

Don't forget to add import for GetLastError :

[DllImport("kernel32.dll")]
static extern uint GetLastError();                

edit : I've just made a try, I get error "ERROR_INVALID_PARAMETER 87 (0x57) The parameter is incorrect.".

So, following this advice, I've read again your code :

You wrote :

   systime.wHour = (ushort)d.Year;

instead of :

   systime.wYear = (ushort)d.Year;

Fixed it, and then, no more error.