C# 修改系统时间

/// <summary>
    /// 同步服务时间
    /// </summary>
    public class SyncServerTime
    {
        //设置系统时间的API函数
        [DllImport("kernel32.dll")]
        private static extern bool SetLocalTime(ref SYSTEMTIME time);

        [StructLayout(LayoutKind.Sequential)]
        private struct SYSTEMTIME
        {
            public short year;
            public short month;
            public short dayOfWeek;
            public short day;
            public short hour;
            public short minute;
            public short second;
            public short milliseconds;
        }

        /// <summary>
        /// 设置系统时间
        /// </summary>
        /// <param name="dt">需要设置的时间</param>
        /// <returns>返回系统时间设置状态，true为成功，false为失败</returns>
        public static bool SetDate(DateTime dt)
        {
            SYSTEMTIME st;

            st.year = (short)dt.Year;
            st.month = (short)dt.Month;
            st.dayOfWeek = (short)dt.DayOfWeek;
            st.day = (short)dt.Day;
            st.hour = (short)dt.Hour;
            st.minute = (short)dt.Minute;
            st.second = (short)dt.Second;
            st.milliseconds = (short)dt.Millisecond;
            bool rt = SetLocalTime(ref st);
            return rt;
        }
    }

运行中发现总是返回false。 
经过研究发现原来时我的程序运行在win8系统上需要管理员权限，然后程序作如下配置即可：