VB Code causes "undo" to stop functioning

I've added the following code to highlight cells when they change

Private Sub Worksheet_Change(ByVal Target As Range)
Const WS_RANGE As String = "A1:IV65536"

 

On Error GoTo ws_exit:

Application.EnableEvents = False

If Not Intersect(Target, Me.Range(WS_RANGE)) Is Nothing Then

With Target

.Interior.ColorIndex = 3

End With





End If

Const WS_RANGE_B As String = "X2:AA5000"

 If Not Intersect(Target, Me.Range(WS_RANGE_B)) Is Nothing Then

With Target

.Interior.ColorIndex = 27

End With





End If

ws_exit:

Application.EnableEvents = True

End Sub

All works as I want but the "undo" function in excel is now not working. When I remove the code it works again?
Any ideas

Thanks
Rory

Good afternoon Rory Murphy

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It is unfortunate that using macros usually clears the undo stack - most, but not all instructions will cause this to happen. As your macro fires every time a change is made to your worksheet, the undo is constantly being cleared.

There is no workaround. Choose to live without your macro firing at every change, or choose to live without the undo functionality.

HTH

DominicB

FYI

http://www.jkp-ads.com/Articles/UndoWithVBA00.asp