Hi Som

You need write a piece of code. From the menu go to
Tools--Macro--Visual Basic Editor--
Select Worksheet and copy the below code

Private Sub Workbook_Open()
If DateDiff("d","12/Mar/2009",Date) < -1 Then
Application.ActiveWorkbook.Close
End If
End Sub

This will only allow the workbook to be used upto Mar 12th. Password protect
the Visual Basic Editor before you distribute.

Jacob Skaria
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