Now I have

Code:
Option Explicit
Dim TimeS As String

Private Sub Command1_Click()

TimeS = TimeS + 0.01
Label1.Caption = Format(TimeS, "#######00:00:00")

End Sub

Private Sub Form_Load()
TimeS = 0

End Sub
But the format does not work label1 remains at 00:00:00 no matter how many times I click command1, that is whatever the value of TimeS is makes no difference