Hi.

This is the situation: I'm creating an Ajax comment form for my site. At first I solve it with writing a BaseExtension class, that processed post request from the page, and that worked. But then I've decided to add AST.NET Captcha module. So, I've edited my form, added a code-behind file with event handler for submit action. Handler calls function, that verifies the captcha-input field value and, if true, have to create new Document under certain node.

Form:

        <form id="reviewForm" class="reviewForm" runat="server">
            <asp:ScriptManager ID="ScriptManager" runat="server"/>
            <asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" runat="server">
                <Triggers>
                    <asp:AsyncPostBackTrigger ControlID="submit" />
                </Triggers>
                <ContentTemplate>
                    <fieldset>
                    <h2>    </h2>
            
                    <label>
                        <span> :</span>
                        <input value="" name="name"/>
                    </label>
                    <label>
                        <span>E-mail:</span>
                        <input value="" name="email"/>
                    </label>
                    <label>
                        <span>:</span>
                        <textarea name="comment"></textarea>
                    </label>
                    </fieldset>
                    <fieldset>
                    <label>
                        <span>  :</span>
                        <input autocomplete="off" id="CaptchaInput" name="captcha" maxlength="5" runat="server"/>
                    </label>
                    <cc1:CaptchaControl ID="CaptchaCode" runat="server"
                        CaptchaBackgroundNoise="Low" CaptchaLength="5"
                        CaptchaHeight="40" CaptchaWidth="120"
                        CaptchaLineNoise="None" CaptchaMinTimeout="5"
                        CaptchaMaxTimeout="240" FontColor = "#4e5da1" />
                    </fieldset>
                                       
                  <button id="submit" type="button" runat="server"></button>
                  
                </ContentTemplate>
            </asp:UpdatePanel>
        </form>

Code behind fragment:

...
using umbraco;
using umbraco.webservices;
using umbraco.cms.businesslogic.web;
using umbraco.presentation.nodeFactory;
namespace CommentForm
{
    public partial class Itemmaster : System.Web.UI.MasterPage
    {
        ...
        protected void Submit_Clicked(object sender, EventArgs e)
        {
            System.Threading.Thread thread = new System.Threading.Thread(() =>
            {
                CaptchaCode.ValidateCaptcha(CaptchaInput.Value);
                if (CaptchaCode.UserValidated)
                {
                    CaptchaInput.Value = "RIGHT!"; // -- works;
                    Node root = new Node(-1); // -- fails!;
                }
                else
                {
                    CaptchaInput.Value = "WRONG!";
                }
            });
            thread.SetApartmentState(System.Threading.ApartmentState.STA);
            thread.Start();
        } 
    ...
    }
}

Umbraco 4.5.2, .NET 3.5

All this works partially: the Captcha verifies without problems and I can, for example, place text "Success" or "Error" back to page. But since I need to create new Document, I try to get current node's Id. And when I add any code, that uses Umbraco API, I receive:

Uncaught Sys.WebForms.PageRequestManagerServerErrorException: Sys.WebForms.PageRequestManagerServerErrorException: An unknown error occurred while processing the request on the server. The status code returned from the server was: 0 

I'm new to .NET and I hope for your help. Thanks.