You can use a Window Script Host popup methode to popup a message and the message box will terminate itself after a defined time (second).
This methode is not an Event driven. You have to plan out the time for the Message box to close.
Dim WshShell
Set WshShell = WScript.CreateObject("WScript.Shell")
' Displays a message for 3 seconds
WshShell.popup "Hello", 3