The following example changes the appearance of the y AxisGrid line style.
Private Sub Command1_Click()
With MSChart1.Plot.Axis(VtChAxisIdY)
.CategoryScale.Auto = False
.ValueScale.MajorDivision = 10
.ValueScale.MinorDivision = 5
.AxisGrid.MajorPen.Style = VtPenStyleSolid
.AxisGrid.MajorPen.VtColor.Green = 255
.AxisGrid.MajorPen.Width = 2
.AxisGrid.MinorPen.Style = VtPenStyleDashed
.AxisGrid.MinorPen.VtColor.Red = 255
.AxisGrid.MinorPen.Width = 1
.AxisGrid.MinorPen.Cap = VtPenCapRound
End With
End Sub