Determines a color for an E3Chart's horizontal grid. Default value of this property is gray (RGB(192, 192, 192)). Example:

Sub CommandButton1_Click()
  Set E3Chart1 = Screen.Item("E3Chart1")
  Old = E3Chart1.HorGridColor
  MsgBox "Next"
  E3Chart1.HorGridColor = RGB(255, 0, 0)
  MsgBox "Next"
  E3Chart1.HorGridColor = RGB(0, 0, 255)
  MsgBox "Return"
  E3Chart1.HorGridColor = Old
End Sub