SetFocus(), or Focus() on textbox not working

 I have the following littel piece of code:
 
 
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load


If Not Page.IsPostBack() Then
LoadFields()
UpdateCheck()
If a.text = "1" then

'txtRating.Focus()
'Page.SetFocus(txtRating)
Else

'txtRating.Focus()
'Page.SetFocus(txtRating)
End If
Else

end sub ...