Test with multipartformdata

gistfile1.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;

namespace DownloadTest
{
    public class Class1
    {
        public void UsingDownloadExample()
        {
            using (var downFile = Download("http://static.tibia.com/download/tibia1076.tgz"))
            {
                
            }
        }
        public Stream Download(string link)
        {
            try
            {
                using (HttpWebResponse response = CreateRequest(link))
                {
                    if (response.StatusCode == HttpStatusCode.OK)
                    {
                        return response.GetResponseStream();
                    }
                    else
                    {
                        // Tratar outros status codes
                        return null;
                    }
                }
            }
            catch (WebException ex)
            {
                Console.Error.Write(ex.ToString());
                return null;
            }
        }

        public HttpWebResponse CreateRequest(string link, string postArgs = null)
        {
            HttpWebRequest request;
            try
            {
                request = (HttpWebRequest) WebRequest.Create(link);

                request.ContentType = "";
                request.Method = "GET";// GET
                request.Timeout = 30*1000;// timeout in milliseconds
                //request.Headers.Add("x-teste", "lol");

                if (request.Method.ToLower() == "post")
                {
                    //var multipart = new MultipartFormDataContent();
                    using (Stream reqStream = request.GetRequestStream())
                    {
                        byte[] byteArray = Encoding.UTF8.GetBytes(postArgs);
                        reqStream.Write(byteArray, 0, byteArray.Length);
                        reqStream.Close();
                    }
                }
                return (HttpWebResponse) request.GetResponse();
            }
            catch (WebException ex)
            {
                throw ex;
            }
        }
    }
}