Private Declare Function SQLDataSources Lib "ODBC32.DLL" (ByVal _
        henv As Long, _
        ByVal fDirection As Integer, _
        ByVal szDSN As String, _
        ByVal cbDSNMax As Integer, _
        pcbDSN As Integer, _
        ByVal szDescription As String, _
        ByVal cbDescriptionMax As Integer, _
        pcbDescription As Integer) _
        As Integer
 
Private Declare Function SQLAllocEnv Lib "ODBC32.DLL" ( _
        env As Long) _
        As Integer
 
Const SQL_SUCCESS As Long = 0
Const SQL_FETCH_NEXT As Long = 1
 
Private Sub Form_Load()
 
  GetDSNsAndDrivers
 
End Sub
 
Sub GetDSNsAndDrivers()
    Dim i As Integer
    Dim sDSNItem As String * 1024
    Dim sDRVItem As String * 1024
    Dim sDSN As String
    Dim sDRV As String
    Dim iDSNLen As Integer
    Dim iDRVLen As Integer
    Dim lHenv As Long         'Zugriffsnummer zur Umgebung
 
    On Error Resume Next
    cboDSNList.AddItem "(None)"
 
    'DSNs abrufen
    If SQLAllocEnv(lHenv) <> -1 Then
        Do Until i <> SQL_SUCCESS
            sDSNItem = Space(1024)
            sDRVItem = Space(1024)
            ' Aufruf der API Funktion zur Ausgabe der nächsten ODBC Verbindung
            i = SQLDataSources(lHenv, SQL_FETCH_NEXT, sDSNItem, 1024, iDSNLen, _
              sDRVItem, 1024, iDRVLen)
            sDSN = Left(sDSNItem, iDSNLen)
            sDRV = Left(sDRVItem, iDRVLen)
 
            If sDSN <> Space(iDSNLen) Then
                debug.print sDSN
            End If
        Loop
    End If
 
 
End Sub