There is know way for Excel to remember you have shown your message box.
What you will have to do is store a piece of data in a cell. For example, if
the message box hasn't been shown yet, cell A1 will equal FALSE and when the
workbook opens it will check that cell to determine if the msgbox needs to be
shown. Hope this helps! If so, let me know, click "YES" below.

Private Sub Workbook_Open()

If Sheets("Sheet1").Range("A1").Value = False Then
MsgBox "Please read the instruction first.", vbInformation
Sheets("Sheet1").Range("A1").Value = True
End If

End Sub
--
Cheers,
Ryan


"John" wrote:

Hi Everyone
Is it possible to have a popup window ( Msgbox ) that will open only one time.
The first time the workbook will be open, I would like to show the message
"Please read the instruction first".
I don't want the message to keep opening every time the workbook is open.
Regards
John

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