Allow images in AtomPub ASPNET Web Api Server

I'm trying to create an Atompub service with ASP.NET WEB API, all it's ok but when I try to post any image from Windows Live Writer I get an error "The blog doesn't allow the image load" I'm reading the ietf doc.

My services controller code:

public class ServicesController : ApiController{    public HttpResponseMessage Get()    {        var serviceDocument = new ServiceDocument();        var workSpace = new Workspace        {            Title = new TextSyndicationContent("Nicoloco Site"),            BaseUri = new Uri(Request.RequestUri.GetLeftPart(UriPartial.Authority))        };        var posts = new ResourceCollectionInfo("Nicoloco Blog",                                               new Uri(Url.Link("DefaultApi", new { controller = "blogapi" })));        posts.Accepts.Add("application/atom+xml;type=entry");        var images = new ResourceCollectionInfo("Images Blog",                                                new Uri(Url.Link("DefaultApi", new { controller = "images" })));        images.Accepts.Add("image/png");        images.Accepts.Add("image/jpeg");        images.Accepts.Add("image/jpg");        images.Accepts.Add("image/gif");        var categoriesUri = new Uri(Url.Link("DefaultApi", new { controller = "tags", format = "atomcat" }));        var categories = new ReferencedCategoriesDocument(categoriesUri);        posts.Categories.Add(categories);        workSpace.Collections.Add(posts);        workSpace.Collections.Add(images);        serviceDocument.Workspaces.Add(workSpace);        var response = new HttpResponseMessage(HttpStatusCode.OK);        var formatter = new AtomPub10ServiceDocumentFormatter(serviceDocument);        var stream = new MemoryStream();        using (var writer = XmlWriter.Create(stream))        {            formatter.WriteTo(writer);        }        stream.Position = 0;        var content = new StreamContent(stream);        response.Content = content;        response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/atomsvc+xml");        return response;    }}

The http GET Request generate the follow XML:

<?xml version="1.0" encoding="utf-8"?><app:service     xmlns:a10="http://www.w3.org/2005/Atom"     xmlns:app="http://www.w3.org/2007/app"><app:workspace xml:base="http://localhost:53644/"><a10:title type="text">Nicoloco Site</a10:title><app:collection href="http://localhost:53644/api/blogapi"><a10:title type="text">Nicoloco Blog</a10:title><app:accept>application/atom+xml;type=entry</app:accept><app:categories href="http://localhost:53644/api/tags?format=atomcat" /></app:collection><app:collection href="http://localhost:53644/api/images"><a10:title type="text">Images Blog</a10:title><app:accept>image/png</app:accept><app:accept>image/jpeg</app:accept><app:accept>image/jpg</app:accept><app:accept>image/gif</app:accept></app:collection></app:workspace></app:service>

But I can't publish images using this service.

Best regards.