atlas 老提示 Unknown error!

Question

代码是这样的：
 
<atlas:ScriptManager ID="ScriptManager1" runat="server" EnablePartialRendering="true">
                 </atlas:ScriptManager>
                
                 <asp:TextBox ID="TextBox_title" runat="server"   class="in4"  OnTextChanged="TextBox_title_TextChanged" AutoPostBack="True"></asp:TextBox> 
                      
                      
                 <atlas:UpdatePanel ID="UpdatePanel1" runat="server">
                 
                    <ContentTemplate>
                       
                         <asp:Label ID="Label_has" runat="server"></asp:Label>
                    </ContentTemplate> 
                    <Triggers>                        <atlas:ControlEventTrigger ControlID="TextBox_title" EventName="TextChanged" />
                    </Triggers>   
                 </atlas:UpdatePanel>
按网上文章写的都有问题，大家帮忙看看！