strComputer = "."
Set objWMIService = GetObject("winmgmts:" _
& "{impersonationLevel=impersonate}!\\" & _
        strComputer & "\root\cimv2" )

Set colMonitoredEvents = objWMIService.ExecNotificationQuery _
    ("SELECT * FROM __InstanceModificationEvent WITHIN 20 WHERE " _
& "TargetInstance ISA 'CIM_DataFile' and " _
& "TargetInstance.Name='R:\\Mon Rép\\MonFichier.xls'" )

Do
    Set objLatestEvent = colMonitoredEvents.NextEvent
    Wscript.Echo "Le fichier " & objLatestEvent.TargetInstance.Name & " a été modifié."
Loop