PingTest Problem

I copied this code off the internet. It compiles fine but when I run it, I get the error below. I am running a Windows 2000 machine and using Microsofts Visual C# 2005 Beta. Thanks for any help you can give me!! Error message: System.Net.NetworkInformation.PingException: An exception occurred during a Ping request. ---> System.EntryPointNotFoundException: Unable to find an entry point named 'IcmpCreateFile' in DLL 'iphlpapi.dll'. at System.Net.NetworkInformation.UnsafeNetInfoNativeMethods.IcmpCreateFile() at System.Net.NetworkInformation.Ping.InternalSend(IPAddress address, Byte[] buffer, Int32 timeout, PingOptions options, Boolean async) at System.Net.NetworkInformation.Ping.ContinueAsyncSend(Object state) --- End of inner exception stack trace --- I looked for the 'iphlpapi.dll' and it is in the WINNT\system32 directory. Here is the code: namespace PingTest { partial class Form1 : Form { public Form1() { InitializeComponent(); } public void StartPingButton_Click(object sender, EventArgs e) { Ping pingSender = new Ping(); pingSender.PingCompleted += new PingCompletedEventHandler(PingCompletedCallback); string data = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"; byte[] buffer = Encoding.ASCII.GetBytes(data); int timeout = 12000; PingOptions options = new PingOptions(64, true); richTextBox1.Text = "Time to Live: " + options.Ttl + "ms" + "\r\n" + "Dont Fragment: " + options.DontFragment; pingSender.SendAsync(textBox1.Text, buffer, timeout, options); }//end StartPingButton public void PingCompletedCallback(object sender, PingCompletedEventArgs e) { if (e.Cancelled) { richTextBox1.Text = "Ping Cancelled."; } if (e.Error != null) { richTextBox1.Text = "Ping Failed. " + "\r\n" + e.Error.ToString(); } PingReply reply = e.Reply; if (reply.Status == IPStatus.Success) { richTextBox1.Text = "Address: " + reply.Address.ToString(); } }// end pingcompletedcallback private void ResetButton_Click(object sender, EventArgs e) { Application.Exit(); } }//end Class Form }//end namespace