Foro de elhacker.NET

Buenas,
trato de hacer un cliente FTP usando el API wininet y me he quedado un poco atascado...
En un form tengo 4 textbox para introducir el server, el puerto, el user y el pass, un botón para conectar al server y un listbox para listar los archivos y carpetas que contiene.
Cuando conecto, me lista correctamente los archivos y carpetas que contiene el server FTP en la carpeta principal, pero cuando intento abrir una de estas carpetas y listar su contenido (haciendo doble click sobre ella) me devuelve 0, como si estuviese vacía, cuando no lo está.
Dejo el código que tengo y si alguno me pudiese orientar le estaría muy agradecido.

Código:


Option Explicit

Private Declare Function InternetOpen Lib "wininet.dll" Alias "InternetOpenA" _
(ByVal sAgent As String, ByVal lAccessType As Long, ByVal sProxyName As String, _
ByVal sProxyBypass As String, ByVal lFlags As Long) As Long

Private Declare Function InternetConnect Lib "wininet.dll" Alias "InternetConnectA" _
(ByVal hInternetSession As Long, ByVal sServerName As String, ByVal nServerPort As Integer, _
ByVal sUsername As String, ByVal sPassword As String, ByVal lService As Long, _
ByVal lFlags As Long, ByVal lContext As Long) As Long

Private Declare Function FtpFindFirstFile Lib "wininet.dll" Alias "FtpFindFirstFileA" _
(ByVal hFtpSession As Long, ByVal lpszSearchFile As String, _
      lpFindFileData As WIN32_FIND_DATA, ByVal dwFlags As Long, ByVal dwContent As Long) As Long

Private Declare Function InternetFindNextFile Lib "wininet.dll" Alias "InternetFindNextFileA" _
    (ByVal hFind As Long, lpvFindData As WIN32_FIND_DATA) As Long

Public Const INTERNET_OPEN_TYPE_PRECONFIG = 0
Public Const INTERNET_SERVICE_FTP = 1
Public Const INTERNET_FLAG_PASSIVE = &H8000000

Dim hOpen As Long
Dim hConnection As Long
Dim server As String
Dim port As Integer
Dim user As String
Dim pass As String
Dim first_file As Long
Dim next_file As Long
Dim datos As WIN32_FIND_DATA


Private Sub Command1_Click()

hOpen = InternetOpen("MiFTP", INTERNET_OPEN_TYPE_PRECONFIG, vbNullString, vbNullString, 0)
DoEvents

server = ftp_server.Text
port = CInt(ftp_port.Text)
user = ftp_user.Text
pass = ftp_pass.Text

hConnection = InternetConnect(hOpen, server, port, user, pass, INTERNET_SERVICE_FTP, INTERNET_FLAG_PASSIVE, 0)
DoEvents

first_file = FtpFindFirstFile(hConnection, vbNullString, datos, 0, 0)
If first_file <> 0 Then
    List1.AddItem datos.cFileName
    next_file = InternetFindNextFile(first_file, datos)
    Do While next_file <> 0
        List1.AddItem datos.cFileName
        next_file = InternetFindNextFile(first_file, datos)
        DoEvents
    Loop
End If
End Sub



Private Sub List1_DblClick()

Label6.Caption = Label6.Caption & "/" & List1.List(List1.ListIndex)
List1.Clear
If FtpSetCurrentDirectory(hConnection, Label6.Caption & "/") <> False Then

    first_file = FtpFindFirstFile(hConnection, vbNullString, datos, 0, 0)
    If first_file <> 0 Then
        List1.AddItem datos.cFileName
        next_file = InternetFindNextFile(first_file, datos)
        Do While next_file <> 0
            List1.AddItem datos.cFileName
            next_file = InternetFindNextFile(first_file, datos)
            DoEvents
        Loop
    End If
End If
End Sub