You can use the worksheet function = TODAY (), but obviously this will be updated to the current date whenever the workbook is recounted.
, , - , 1729, Workbook_Open:
Private Sub Workbook_Open()
ThisWorkbook.Worksheets("Sheet1").Range("A1").Value = Date
End Sub
, , ( VBA IDE Tools | Digital Signature...) , (. http://msdn.microsoft.com/en-us/library/ms995347.aspx). , , .