<!DOCTYPE html>
<html>
<body>

<form runat="server">
<asp:TextBox id="tb1" AutoCompleteType="FirstName" runat="server" />
<p><br>
Type your first name in the textbox, then press enter and reload the page.</p>
<p>When typing in the first letters of your name the second time, the autocomplete feature should work.</p>
</form>

</body>
</html>