<asp:GridView ID="grdTemp" runat="server" AllowPaging="True"
AutoGenerateColumns="False" DataKeyNames="TIME" Height="40px"
PageSize="8" ShowFooter="True" >
<PagerSettings Mode="NumericFirstLast" />
<RowStyle BackColor="WhiteSmoke" BorderColor="CornflowerBlue" ForeColor="Black"
Height="30px" />
<Columns>
<asp:TemplateField >
<ItemTemplate>
<asp:CheckBox ID="chkSelect" runat="server" />
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="TIME" HeaderText="TIME" /><<pre>FooterStyle BackColor="Silver" Height="25px" />
<PagerStyle BackColor="DarkGray" />
<HeaderStyle BackColor="#000084" Font-Bold="True" ForeColor="White" />
</asp:GridView>
OnCheckedChanged event write the following code
if chk.checked=true then
chk.enabled=false