Referrence error C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace _28155859
{
    class Program
    {
        public static void Main(string[] args)
        {
            // Print SharpPcap version
            string ver = SharpPcap.Version.VersionString;
            Console.WriteLine("SharpPcap {0}, Example5.PcapFilter.cs\n", ver);

            // Retrieve the device list
            var devices = CaptureDeviceList.Instance;

            // If no devices were found print an error
            if (devices.Count < 1)
            {
                Console.WriteLine("No devices were found on this machine");
                return;
            }

            Console.WriteLine("The following devices are available on this machine:");
            Console.WriteLine("----------------------------------------------------");
            Console.WriteLine();

            int i = 0;

            // Scan the list printing every entry
            foreach (var dev in devices)
            {
                Console.WriteLine("{0}) {1}", i, dev.Description);
                i++;
            }

            Console.WriteLine();
            Console.Write("-- Please choose a device to capture: ");
            i = int.Parse(Console.ReadLine());

            var device = devices[i];

            //Register our handler function to the 'packet arrival' event
            device.OnPacketArrival +=
                new PacketArrivalEventHandler(device_OnPacketArrival);

            //Open the device for capturing
            int readTimeoutMilliseconds = 1000;
            device.Open(DeviceMode.Promiscuous, readTimeoutMilliseconds);

            // tcpdump filter to capture only TCP/IP packets
            string filter = "ip and tcp";
            device.Filter = filter;

            Console.WriteLine();
            Console.WriteLine
                ("-- The following tcpdump filter will be applied: \"{0}\"",
                filter);
            Console.WriteLine
                ("-- Listening on {0}, hit 'Ctrl-C' to exit...",
                device.Description);

            // Start capture packets
            device.Capture();

            // Close the pcap device
            // (Note: this line will never be called since
            //  we're capturing infinite number of packets
            device.Close();
        }

        /// <summary>
        /// Prints the time and length of each received packet
        /// </summary>
        private static void device_OnPacketArrival(object sender, CaptureEventArgs e)
        {
            var time = e.Packet.Timeval.Date;
            var len = e.Packet.Data.Length;
            Console.WriteLine("{0}:{1}:{2},{3} Len={4}",
                time.Hour, time.Minute, time.Second, time.Millisecond, len);
        }
    }
}

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