In Excel 2002 event:

Workbook_SheetChange(ByVal Sh As Object, ByVal Target As Range)

Target.Text is the cell's value *after* changing.

How do I get the cell's value *before* the change?

Excel 2002 Help lists no such event. Object Sh seems to be null. And a
Range object doesn't have a "PreviousValue" property, does it?

Two, if that functionality exists, how do I cancel the change and
prevent the cell from updating?

My purpose is: I need to prohibit users from copying cells to targets
that already have data. In that case I want them to rekey the new value
(s) manually. I'm getting burned by people overwriting whole ranges of
data and screwing themselves up. (If they want to copy data to a blank
target, that's OK. Solving the problem by, say, requiring them to lock/
unlock cells would be an impossible kludge.)

It seems that the event above should rather be called
Workbook_AfterSheetChange, shouldn't it? So where's its Before
partner?

Thanks much.

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