The following example sets a blue X marker style for a chart series.
Option Explicit
Option Base 1
Private Sub Command1_Click()
' Display Markers for Series 1.
Dim i As Integer
For i = 1 To MSChart1.Plot.SeriesCollection.Count
With MSChart1.Plot.SeriesCollection _
.Item(i).DataPoints.Item(-1).Marker
.Visible = True
.Size = 20
.Style = VtMarkerStyleX
.FillColor.Automatic = False
.FillColor.Set 0, 0, 255
End With
Next i
End Sub