ActiveChart Selection?

[PossiblyNot]

Hi all

I've been scratching my head over this problem, it seems a little odd. I have a macro that creates and automatically populates an xy chart. On startup it works, but a few minutes in to using the spreadsheet it suddenly stops working and kicks out a 91 error. sometimes it will all of a sudden start working again.

Could it be possible that there's an issue with selecting the active chart, that a few minutes in I click on a cell, or sheet or object that makes the code kick a fuss?

Sub createGraph()
   On Error GoTo ErrHandler
    'Dim xRow As Long
    'xRow = Cells(Rows.Count, "A").End(xlUp).Row
    ActiveSheet.Shapes.AddChart.Select
    ActiveChart.ChartType = xlXYScatterLinesNoMarkers
    ActiveChart.SetElement (msoElementLegendNone)                                   'Debugger sends me here. When I comment it out...
    ActiveChart.SetElement (126)                                                                    'This Errors Out
    ActiveChart.SetElement (msoElementPrimaryValueAxisTitleRotated)         'Then This
    ActiveChart.Axes(xlValue, xlPrimary).AxisTitle.Text = "Age (Ma)"              'Then This
    ActiveChart.ChartArea.Select                                                                        'You get the Pattern...
    ActiveChart.SetElement (msoElementChartTitleAboveChart)
    ActiveChart.ChartTitle.Text = "Biostratigraphy Plot"
    ActiveChart.ChartArea.Select
   
    
    With ActiveChart.Axes(xlValue)
        '.HasAxis(xlCategory) = 1
        '.HasAxis(xlSeries) = 1
        .MinimumScale = 0
        .MaximumScale = 80
        .ReversePlotOrder = True
        .DisplayUnit = xlNone
    End With

I can't quite work out what's up :/ a 91 error means I'm not Setting something somewhere, but ActiveChart can't be Set...

Cheers

Rich