Hide All The Sheets Except Important Sheet

I wanted to force the user to "enable macros." Searching online brought me to the method of hiding all sheets but one and only un-hiding the important sheets if the user accepts macros. This is done with event procedures as shown below ( I stole this code from a webpage and only added unprotect/protect workbook and made the Hideall and Showall subs private also since I don't want the user to have any idea what's going on):

The code below starting with BEGIN works but my problem is I need to add some additional stuff to the WorkBook_BeforeClose procedure. What I added to the BeforeClose procedure is a series of IF statements that follow this form:


If IsEmpty(Range("C9").Value) = True Then
MsgBox "Please enter data in this Cell C9", vbExclamation + vbOKOnly, "Validation"
Cancel = True
End if
The problem occurs if the User attempts to close without entering the required data. This will correctly trigger the above IF statements as desired. However, after Canceling, if the user decides to Save (without closing, by say clicking the floppy disk button in the upper left), then "HideAll" is executed which I do not want. I assume this is because bIsClosing has been set to TRUE and was never reset after the IF statements triggered a Cancel? Is this correct? How can I fix this? I tried adding a bIsClosing = False line at the end of every IF statement, but I think that just made things more screwy.

BEGIN


Private Sub Workbook_BeforeClose(Cancel As Boolean)

bIsClosing = True
End Sub


Private Sub Workbook_BeforeSave(ByVal SaveAsUI As Boolean, Cancel As Boolean)
If Cancel = True Or bIsClosing = False Then Exit Sub
Run "HideAll"........................