Worksheet_Change Never FIres
===

I am using VBA to alter Excel and have the following simple event handler inside the Sheet1:

    Private Sub Worksheet_Change(ByVal Target As Range)
        MsgBox "HI"
    End Sub

This never fires though, ever. I have tested in the Immediate Window:

> ?Application.EnableEvents

which ultimately returns True, so it should fire. Does anyone know why this doesn't want to fire at all?