Invalid Parameter - VBA Chart Color - excel

Question

Recently I have automated the coloring of a series of charts based off 3 key conditions. If they are "Planned", "Forced", or "Other" - the chart color will be automated rather than being a manual process. However, recently it has stopped working even though there has been no change in my code.
I reviewed my code and it has highlighted one of my modules, with the below line being the culprit supposedly.
ElseIf InStr(outRng.Offset(tabRowloop, 5 + ((tabcolloop - 1) * 5)), "Planned") > 0 Then
serobj.Points(tabRowloop + 1).Format.Fill.ForeColor.RGB = RGB(30, 65, 100)
If I comment out this line, the code runs but the coloring does not work. The loop functions are fine, but I cannot understand how the coloring of my points causes an "Invalid Parameter" error.
Is anyone able to provide any guidance on what the cause could be?
'Code for Recolor Chart Module
Dim tabRowloop As Integer
Dim tabcolloop As Integer
Dim seriesnum As Integer
Dim serobj As Series
For tabcolloop = 1 To maxGanttBarsPerSite Step 1
seriesnum = stupidRangeIndexThingy(tabcolloop)
Set serobj = chobj.Chart.FullSeriesCollection(seriesnum)
serobj.Format.Fill.ForeColor.RGB = RGB(50, 50, 50)
tabRowloop = 0
Do While Len(outRng.Offset(tabRowloop, 1))
If (Len(outRng.Offset(tabRowloop, 1 + ((tabcolloop - 1) * 5))) > 0) Then
Debug.Print tabRowloop & "," & tabcolloop
If InStr(outRng.Offset(tabRowloop, 5 + ((tabcolloop - 1) * 5)), "Forced") > 0 Then
serobj.Points(tabRowloop + 1).Format.Fill.ForeColor.RGB = RGB(192, 0, 0)
ElseIf InStr(outRng.Offset(tabRowloop, 5 + ((tabcolloop - 1) * 5)), "Planned") > 0 Then
serobj.Points(tabRowloop + 1).Format.Fill.ForeColor.RGB = RGB(30, 65, 100)
'problem is with the above line
Else
serobj.Points(tabRowloop + 1).Format.Fill.ForeColor.RGB = RGB(247, 150, 70)
End If
End If
tabRowloop = tabRowloop + 1
Loop
Next
'Sort table - Synergy first then by name
Call SortFinalTable(numUnitsFound)
'Turn on calc and redraw
Application.Calculation = xlCalculationAutomatic
Application.ScreenUpdating = True
End Sub

Answer 1

You'll get an Invalid Parameter error if your index for the Points object is out of range. If it fails on the first loop when tabRowLoop still equals 0, it suggests that serobj doesn't have any point. If it fails on later loops, it's because you're exceeding the number of points in the series. When stepping through the code, after the serobj variable has been set, try confirming which series has been picked up by running some debug/immediate commands.
print serobj.Points.Count