Hi, Dude!

It seems that the Encoding is messing with the binary data you are downloading. When the data is encoded from a byte array to a string, some sequences of bytes are changed, making your file to become currupted.

I think that the following code will make it:

private void DownloadFile(string url)
{
    string fileLocationWhenDownloaded = Path.Combine("C:\\", Path.GetFileName(url));

    byte [] downloadedBytes;
        
    WebClient webClient = new WebClient();
    downloadedBytes = webClient.DownloadData(url);

    
    FileStream fs = new FileStream(fileLocationWhenDownloaded, FileMode.CreateNew);
    fs.Write(downloadedBytes, 0, downloadedBytes.Length);
    fs.Flush();
    fs.Close();
}

call it passing the url of the file to be downloaded:

DownloadFile("http://YourSite/YourFile.Zip");

HTH.