Excel 2000 vs 97 code

Giganews Newsgroups
Subject: Excel 2000 vs 97 code
Posted by:  Carl Johnson (bjohns…@woh.rr.com)
Date: Wed, 08 Oct 2003

Several weeks ago I inquired in this news group about how to ensure that
when the end user closed a spreadsheet that all the data was entered. I got
an excellent response from Ron de Bruin that worked great on my machine
where I have Excel 2000 however when I took it to work it would not work,
they have '97. How can I alter the following code to get it to work on '97?
Thank you in advance.

Private sub WorkBook_Before Close(Cancel As Boolean)
    If Application.WorksheetFunction.CountA(Sheets("Sheet1")
..Range("A1:A10")) < 10 Then
    MgsBox "You must fill in all the cells"
    Cancel = True
End If
End sub