Large dimensions image cannot be displayed in bitmapimage in Silverlight

I need show 2,54MB jpeg image (15232 x 7912 pixels, 96DPI) in Silverlight 5.0.

I using BitMapImage component and image not showing. When opening a browser window by doubleclick on image, will sometimes appear.

When i have breakpoint in ImageFailed handler i see in eventargs ErrorException: "AG_E_NETWORK_ERROR" (InnerException is null).

What does it mean?

Thanks and sorry for my english. Code below.

    string url = await GetDocumentURLAsync(...);
    bitmapImage.UriSource = new Uri(url);
    image.Source = bitmapImage;

    image.ImageFailed += (sender, e) =>
    {
        System.Diagnostics.Debug.WriteLine(e.ErrorException);
    };