Also you can add a reference to Microsoft Internet Controls and the
following code:

Option Explicit

Dim WithEvents SW As ShellWindows

Private Sub Form_Load()

    Set SW = New ShellWindows

End Sub

Private Sub SW_WindowRegistered(ByVal lCookie As Long)
Dim IE As InternetExplorer, hW As Long
Dim V1, V2

    V1 = lCookie
    V2 = Null
    Set IE = SW.FindWindow(V1, V2, SWC_BROWSER, hW, SWFO_COOKIEPASSED Or
SWFO_NEEDDISPATCH)

    If Not IE Is Nothing Then Debug.Print "New Explorer window."

End Sub

Be carefull because SW_WindowRegistered is called when a Internet Explorer o
Window Explorer or may other windows are opened. But is not called when a
Windows Explorer windows becomes a Internet Explorer window in vers >= 4.

ShellWindows is a collection of all IE, Windows Explorer (and may be other)
windows.

--
Eduardo Morcillo
Free ActiveX Controls: http://www.*-*-*.com/