VBA code does not work in Excel 2007

Hello,

I'm a beginner with Excel programming. I inherited a report developed in Excel 2003. The report has a few charts. The axes on the chart change based on a VBA code. The scale changes in 2003 but does not work in 2007. So the graph appears to cut of the values falling out of range. Here is the code. Any help is appreciated.

Private Sub ComboBox1_Change()
On Error GoTo 1
With Worksheets("CPC, % Supply-NPSR").ChartObjects(2).Chart.Axes(xlValue)
.MaximumScale = Range("AF2").Value
.MinimumScale = Range("AF3").Value
End With

With Worksheets("CPC, % Supply-NPSR").ChartObjects(1).Chart.Axes(xlValue)
.MaximumScale = Range("AE2").Value
.MinimumScale = Range("AE3").Value
End With