You should use a Stream Reader to obtain the data from the Webrequest. Here is an example you can adapt to your code.
private void Main_Load(object sender, EventArgs e)
{
WebRequest request = WebRequest.Create("Your XML File Location Here");
request.Credentials = CredentialCache.DefaultCredentials;
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream iDataStream = response.GetResponseStream();
StreamReader reader = new StreamReader(iDataStream);
string eresponse = reader.ReadToEnd();
MessageBox.Show(eresponse);
reader.Close();
iDataStream.Close();
response.Close();
}
You can see the original answer to this similar question on this other question which you may find helpful.
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