Estoy descargando un archivo zip usando el programa c # y me aparece el error

at System.IO.Compression.ZipArchive.ReadEndOfCentralDirectory()
   at System.IO.Compression.ZipArchive.Init(Stream stream, ZipArchiveMode mode,
Boolean leaveOpen)
   at System.IO.Compression.ZipArchive..ctor(Stream stream, ZipArchiveMode mode,
 Boolean leaveOpen, Encoding entryNameEncoding)
   at System.IO.Compression.ZipFile.Open(String archiveFileName, ZipArchiveMode
mode, Encoding entryNameEncoding)
   at System.IO.Compression.ZipFile.ExtractToDirectory(String sourceArchiveFileN
ame, String destinationDirectoryName, Encoding entryNameEncoding)
   at System.IO.Compression.ZipFile.ExtractToDirectory(String sourceArchiveFileN
ame, String destinationDirectoryName)

Aquí está el programa

    response = (HttpWebResponse)request.GetResponse();
    Stream ReceiveStream = response.GetResponseStream();
    byte[] buffer = new byte[1024];
    FileStream outFile = new FileStream(zipFilePath, FileMode.Create);
    int bytesRead;
    while ((bytesRead = ReceiveStream.Read(buffer, 0, buffer.Length)) != 0)
        outFile.Write(buffer, 0, bytesRead);
    outFile.Close();
    response.Close();
    try
    {
        ZipFile.ExtractToDirectory(zipFilePath, destnDirectoryName);
    }
    catch (Exception e)
    {
        Console.WriteLine(e.ToString());
        Console.ReadLine();
    }

No entiendo el error. ¿Alguien puede explicar esto? Gracias MR