Private Sub Worksheet_Calculate()
How can I add these two lines to this code below

Range("M1") = Now
Range("O1") = Now

When I try to add them the code just hangs

Thanks



Dim i As Integer
For i = 4 To 500
Call Worksheet_Change(Cells(i, 9))
Next
End Sub


Private Sub Worksheet_Change(ByVal Target As Range)
Dim Line As Range
On Error Resume Next
With Target
If .Row = 4 And .Row <= 500 And .Column = 9 Then
Set Line = Range(Cells(.Row, 1), Cells(.Row, 13))
Select Case .Value
Case vbNullString
Line.Interior.ColorIndex = xlNone
Case "POQA"
Line.Interior.ColorIndex = 15
Case "IN PROCESS"
Line.Interior.ColorIndex = 22
Case "INSERTING"
Line.Interior.ColorIndex = 40
Case "STMTHAND"
Line.Interior.ColorIndex = 38
Case "OD-M34"
Line.Interior.ColorIndex = 50
Case Else
Line.Interior.ColorIndex = 20
End Select
End If
End With
End Sub