Public Class Form1
    Dim WithEvents NoExplorer As New clsShellWindow
 
    Private Sub NoExplorer_OnError(ByVal Ex As System.Exception) Handles _
      NoExplorer.OnError
        'Bei einem Fehler 
        MsgBox(Ex.Message)
    End Sub
 
    Private Sub NoExplorer_OnExplorerOpen() Handles NoExplorer.OnExplorerOpen
        'Wird immer aufgerufen wenn ein Explorer geöffnet wird
        MsgBox("Explorer gestartet.")
    End Sub
End Class
Public Class clsShellWindow
    Private WithEvents Window As SHDocVw.ShellWindows
    Private SH As Shell32.Shell
    Public Event OnError(ByVal Ex As Exception)
    Public Event OnExplorerOpen()
 
    Public Sub New()
        Try
            SH = New Shell32.Shell
            Window = SH.Windows
        Catch ex As Exception
            RaiseEvent OnError(ex)
        End Try
 
    End Sub
    Private Sub Window_WindowRegistered(ByVal lCookie As Integer) Handles _
      Window.WindowRegistered
        Try
            Dim WB As SHDocVw.InternetExplorer = Window.Item(Window.Count - 1)
            WB.Quit() 'Explorer sofort wieder Beenden
            RaiseEvent OnExplorerOpen()
        Catch ex As Exception
            RaiseEvent OnError(ex)
        End Try
    End Sub
End Class