I am trying to doubleclick checkbox26 and make value of cell D10 = "N/A" as
well as clear tick in checkbox26. But then if the user later wants to go
back and single click checkbox26 I need to clear the "N/A" and have the
checkbox operate as normal. Here's what I have:

Private Sub CheckBox26_Click()
Range("D10").Value = "N/A"
End Sub

Private Sub CheckBox26_DblClick(ByVal Cancel As ReturnBoolean)
Range("D10").Value = "N/A"
CheckBox26.Value = False
End Sub

It works one time but then will not clear D10.