LayoutTemplate不包含带有用户名ID Userd的IEditableTextControl

Question

即时制作一个网站，我以前从未使用过visual studio 2012，并且难以修复出现的错误，是否有人知道这个错误是什么？

https://imagizer.imageshack.us/v2/821x409q90/661/407a87.png

   <asp:Login runat="server" ViewStateMode="Disabled" RenderOuterTable="false">
        <LayoutTemplate>
            <p class="validation-summary-errors">
                <asp:Literal runat="server" ID="FailureText" />
            </p>
            <fieldset>
                <legend>Log in Form</legend>
                <ol>
                    <li>
                        <asp:Label runat="server" AssociatedControlID="UserName">Username</asp:Label>
                        <asp:TextBox runat="server" ID="UserName" Width="266px" />
                        <asp:RequiredFieldValidator runat="server" ControlToValidate="UserName" CssClass="field-validation-error" ErrorMessage="Please enter your username." />
                    </li>
                    <li>
                        <asp:Label runat="server" AssociatedControlID="Password">Password</asp:Label>
                        <asp:TextBox runat="server" ID="Password" TextMode="Password" Width="263px" />
                        <asp:RequiredFieldValidator runat="server" ControlToValidate="Password" CssClass="field-validation-error" ErrorMessage="Please enter your password." />
                    </li>
                    <li>
                        <asp:CheckBox runat="server" ID="RememberMe" />
                        <asp:Label runat="server" AssociatedControlID="RememberMe" CssClass="checkbox">Remember me?</asp:Label>
                    </li>
                </ol>
                <asp:Button runat="server" CommandName="Login" Text="Log in" />
            </fieldset>
        </LayoutTemplate>
    </asp:Login>