Private Const TM_TEXT As String = "Запустить макрос?" + vbCrLf + "Окно автоматически закроется через 2 секунды."
Private Const TM_TITLE As String = "Макрос"
Private Const TM_DURATION As Long = 2 'seconds

Sub Autostart()
Dim WSH As Object

    Set WSH = CreateObject("WScript.Shell")
    
    Select Case WSH.Popup(TM_TEXT, TM_DURATION, TM_TITLE, 0)
        Case vbOK
            frmBrowse.Show
 
        Case -1
        Set WSH = Nothing
        
    End Select

End Sub