来自ASP.NET的WebClient给出“远程主机强制关闭了现有连接”错误

我想把电话列表贴到星号框里

从一个控制台应用程序中,它可以工作:

 class Program
  {
    static void Main(string[] args)
    {


        Console.WriteLine( HttpPost());
        System.Threading.Thread.Sleep(10000);
    }

    public static string HttpPost()
    {
        var URI = @"http://sip.ligmarine.com/admin/config.php?quietmode=on&type=tool&display=printextensions";
        var Parameters = "display=printextensions&quietmode=on&type=tool&core=core&featurecodeadmin=featurecodeadmin&paging=paging";
        var retVal = "";
        WebClient wc = new WebClient();

        wc.Headers.Add("Authorization", "Basic " + Convert.ToBase64String(Encoding.ASCII.GetBytes("maint:password")));
        wc.Headers.Add("referer", @"http://sip.ligmarine.com/admin/config.php?type=tool&display=printextensions");
        wc.Headers.Add("Content-Type", "application/x-www-form-urlencoded");

        retVal = Convert.ToBase64String(Encoding.ASCII.GetBytes("maint:password"));
        //Console.Write("Resulting Request Headers: ");
        //Console.WriteLine(wc.Headers.ToString());
        byte[] byteArray = Encoding.ASCII.GetBytes(Parameters);
        //Console.WriteLine("Uploading to {0} ...", URI);
        // Upload the input string using the HTTP 1.0 POST method.
        byte[] responseArray = wc.UploadData(URI, "POST", byteArray);
       // Console.WriteLine("\nResponse received was {0}", );

        retVal = Encoding.ASCII.GetString(responseArray);

        return retVal;
    }
}

从我们的iis6托管的ASP.NET页面我得到

远程主机强制关闭了现有连接 描述:当前网站执行期间发生未处理的异常
请求。请查看堆栈跟踪以获取有关错误和
它起源于代码。

 Exception Details: System.Net.Sockets.SocketException: An existing connection was      forcibly closed by the remote host

 Source Error:

 Line 37:         //Console.WriteLine("Uploading to {0} ...", URI);
 Line 38:         // Upload the input string using the HTTP 1.0 POST method.
 Line 39:         byte[] responseArray = wc.UploadData(URI, "POST", byteArray);
 Line 40:         // Console.WriteLine("\nResponse received was {0}", );
 Line 41: 

httppost方法与页面加载完全相同:

protected void Page_Load(object sender, EventArgs e)
{

    var ret = HttpPost();
    Response.Write(ret);
}