ftp-file transfer verwenden vb.net ohne third-party-tools

Schreibe ich den code mit vb.net für Datei-transfer vom remote-Computer zum lokalen Rechner aus Verwendung von tools von Drittanbietern

Dies ist mein code

Dim reqFTP As FtpWebRequest
    Dim filepath As String
    Dim filename As String
    Dim filename1 As String
    Dim ftpserverip As String
    Dim ftpuserid As String
    Dim ftpPassword As String
    Try
        filename1 = TxtRemoteFile.Text
        filepath = TxtLocalFile.Text
        filename = Locfname.Text
        ftpserverip = TxtServerIP.Text
        ftpuserid = TxtUserName.Text
        ftpPassword = TxtPwd.Text
        Dim outputStream As FileStream = New FileStream((filepath + ("\\" + filename)), FileMode.Create)
        reqFTP = CType(FtpWebRequest.Create(New Uri(("ftp://" _
                            + (ftpserverip + ("/" + filename1))))), FtpWebRequest)
        reqFTP.Method = WebRequestMethods.Ftp.DownloadFile
        reqFTP.UseBinary = True
        reqFTP.Credentials = New NetworkCredential(ftpuserid, ftpPassword)
        Dim response As FtpWebResponse = CType(reqFTP.GetResponse, FtpWebResponse)

        outputStream.Close()

    Catch ex As Exception
        MessageBox.Show(ex.Message)
    End Try

aber bin immer Fehler wie" remote server hat einen Fehler zurückgegeben :(550) fi