Private Declare Function InternetGetConnectedState Lib _
  "wininet.dll" (ByRef lpdwFlags As Long, _
  ByVal dwReserved As Long) As Long
Private Declare Function InternetHangUp Lib "wininet.dll" _
  (ByVal dwConnection As Long, ByVal dwReserved As Long) _
  As Long
 
Private Const DIAL_FORCE_ONLINE = 1
Private Const DIAL_FORCE_UNATTENDED = 2
 
Private Type RASCONN
  dwSize As Long
  hRasConn As Long
  szEntryName(256) As Byte
  szDeviceType(16) As Byte
  szDeviceName(128) As Byte
End Type
 
Private Declare Function RasEnumConnectionsA Lib _
  "RasApi32.DLL" (lpRasConn As Any, lbcp As Long, _
  lbcConnections As Long) As Long
 
 
 
Public Function RASDisconnect(ByVal hWnd As Long, _
  Optional ByVal DFÜName As String = "", _
  Optional ByVal DisconnectAll As Boolean) As Boolean
 
  Dim nConnected As Long
  Dim dwFlags As Long
  Dim lpRasConn(255) As RASCONN
  Dim lpcConnections As Long
  Dim lpcb As Long
  Dim hRasConn As Long
  Dim i As Long
  Dim Result As Boolean
 
  Result = False
  If Not DisconnectAll Then
    '(bestimmte) Verbindung trennen
    hRasConn = RASIsConnected(hWnd, DFÜName)
    If hRasConn <> 0 Then
      Result = (InternetHangUp(hRasConn, 0) = 0)
    End If
 
  Else
    'Alle Verbindungen trennen
    nConnected = InternetGetConnectedState(dwFlags, 0)
    If (nConnected) Then
      lpRasConn(0).dwSize = 412
      lpcb = 256 * lpRasConn(0).dwSize
      RasEnumConnectionsA lpRasConn(0), lpcb, lpcConnections
 
      Result = True
      For i = 0 To lpcConnections - 1
        hRasConn = lpRasConn(i).hRasConn
        If InternetHangUp(hRasConn, 0) <> 0 Then _
          Result = False
      Next i
    End If
  End If
 
  RASDisconnect = Result
End Function