FullColumn.Hidden in Worksheet_Change ()

Using Excel 2010, I edit an existing unprotected book and created in the teams event Worksheet_Change()

event EntireColumn.Hidden

, and EntireRow.Hidden

when the data validation cell, but they do not work.

Private Sub Worksheet_Change(ByVal Target As Range)

With Application
    .ScreenUpdating = False
    .EnableEvents = False
End With

If Not Intersect(Target, Range("$C$2")) Is Nothing Then
    Select Case Target.Value
        Case "NO"
            MsgBox "You just changed to HIDE"          '<= Proves it fires
            Range("$C$3").Value = "Invisible"          '<= Does change cell
            Columns("N:O").EntireColumn.Hidden = True  '<= Doesn't hide
        Case "YES"
            MsgBox "You just changed to UNHIDE"        '<= Proves it fires
            Range("$C$3").Value = "Visible"            '<= Does change cell
            Columns("N:O").EntireColumn.Hidden = False '<= Doesn't unhide
    End Select
End If

With Application
    .ScreenUpdating = True
    .EnableEvents = True
End With

End Sub

      

        
        
        
      

    

Event fires since I have MsgBox

to prove it. I can change the values ​​of the cells, etc., but not hiding / showing the column / row.

I copied my code into a new book and it works. So I copied it back to the original book, but as a fresh blank slate and it works. This still doesn't work in the original, significant sheet.

When I copied this into a simple macro it works as needed, hiding the correct columns, but when the button is clicked:

Sub HideThem()
    Columns("N:O").EntireColumn.Hidden = True '<= DOES work
End Sub

      

        
        
        
      

    

I need this to automatically update based on the value of an individual cell. I even tried to call this mini Sub

from the event Worksheet_Change()

but it didn't work either.

Are there any known conflicts with other commands / events, inline buttons, images, merged cells, etc. that might prevent the columns / rows from being hidden?

I tried using a CheckBox

data validator instead of a cell YES/NO

to run the code (as that might be acceptable), but when I try to insert the ActiveX CheckBox

it says it can't insert the object, even in a completely new blank workbook. Could this be a related issue?