Решение:
try
{
string url="http://...";
WebRequest req = WebRequest.Create(url);
WebResponse resp = req.GetResponse();
Stream stream = resp.GetResponseStream();
StreamReader sr = new StreamReader(stream, System.Text.Encoding.Default);
xml = sr.ReadToEnd();
stream.Close();
sr.Close();
}
catch (Exception ex)
{
return;
}