Sub Auto_Open() 
    Dim exdate As Date 
    exdate = "27/06/2007" 
    If Date > exdate Then 
         MsgBox ("This file has expired") 
        ActiveWorkbook.Close 
    End If 
    MsgBox ("You have " & exdate - Date & "Days left") 
End Sub
AS you can see from the code this code is subject to computer system date and one can reject the expiry changing the system date.

Can this date be made online sysytem ie the date will be independent of systems date rather it will take date from online clock from any site.