WebClient security error when accessing the world of warcraft armoury

Answer 1

When running a Silverlight application in a browser, the silverlight application may only make requests to URLs from the same domain as the application was installed from. For instance, if your silverlight app is installed from http://yoursite.com/yourapp.xap, you can only make WebClient requests to other URLs on http://yoursite.com/. Your options here are either create a proxy script that requests the WoW armory from your server, and have your silverlight app hit that proxy, or run the silverlight out-of-browser and request full trust.

Edit: Generally the best option is a cross-domain policy file as explained here. Sadly, It does not appear that wowarmory.com implements the cross-domain policy file.

Answer 2

Hi, you were on the right track, you just need to set the user-agent.

private void button10_Click(object sender, RoutedEventArgs e)
    {
        string url = @"http://eu.wowarmory.com/guild-info.xml?r=Eonar&n=Gifted and Talented"; 
        WebClient wc = new WebClient();

        // HOW DO I ADD A USER AGENT STRING (RESPONSE MAY VARY (I.E. HTML VS XML) IF PAGE THINKS CALL IS NOT CAPABABLE OF SUPPORTING XML TRANSFORMATIONS) 
        //wc.ResponseHeaders["User-Agent"] = "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0)";

        wc.Headers[HttpRequestHeader.UserAgent] = "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0)";
        wc.DownloadStringCompleted += new DownloadStringCompletedEventHandler(wc_DownloadStringCompleted);
        wc.DownloadStringAsync(new Uri(url));    
    }

    void wc_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
    {
        if (e.Error == null)
        {
            string result = e.Result;

            XDocument ArmouryXML = XDocument.Parse(result);

            ShowGuildies(ArmouryXML);
        }
        else
        {
            MessageBox.Show("Something is complaining about security but not sure what!");
        }
    } 

Answer 3

SOLVED - used a WCF service to act as a proxy due to cross domain security and header modification restrictions. Thanks for all the advice.