Private SubYourMemoControlName.Value_GotFocus()
If IsNull(YourMemoControlName.Value) Then
Me.YourMemoControlName.Value = Now() & ": "
Me.YourMemoControlName.SelLength = 0
Else
Me.YourMemoControlName.Value = Me.YourMemoControlName.Value & " " & Now() & ": "
Me.YourMemoControlName.SelStart = Len(Me.YourMemoControlName.Value) + 2
End If
End Sub