codice:
INTERNET_CONNECTION_CONFIGURED
INTERNET_CONNECTION_OFFLINE
INTERNET_CONNECTION_PROXY
INTERNET_RAS_INSTALLED
Private Sub Form_Load()
    Dim flags As Long
    Dim length As Long
    Dim connection_name As String
    Dim connected As Boolean
    Dim ctl As Control
    length = 256
    connection_name = Space$(length)
    connected = InternetGetConnectedStateEx(flags, connection_name,length, 0&)
    For Each ctl In Controls
        If TypeOf ctl Is CheckBox Then ctl.Value = vbUnchecked
    Next ctl
    If connected Then
        lblConnection.Caption = Left$(connection_name,
        InStr(connection_name, Chr$(0)) - 1)
        ' If flags And INTERNET_CONNECTION_CONFIGURED Then
        chkConfigured.Value = vbChecked
        If flags And INTERNET_CONNECTION_LAN Then chkLan.Value =vbChecked
        If flags And INTERNET_CONNECTION_MODEM Then chkModem.Value = vbChecked
        ' If flags And INTERNET_CONNECTION_OFFLINE Then
        chkOffline.Value = vbChecked
        ' If flags And INTERNET_CONNECTION_PROXY Then chkProxy.Value = vbChecked
        ' If flags And INTERNET_RAS_INSTALLED Then
        chkRASInstalled.Value = vbChecked
    End If
End Sub
con questo code scopri quale connessione è attiva poi basta che la disconnetti