string userAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:50.0) Gecko/20100101 Firefox/50.0";
string url = "https://2017godpetuha.ru/wp-content/uploads/2016/06/jubka-polusolnce-150x150.jpg";
// GET запрос
HttpWebRequest request = (HttpWebRequest) WebRequest.Create(url);
request.Method = "GET";
request.UserAgent = userAgent;
HttpWebResponse response = (HttpWebResponse) request.GetResponse();
StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8);
string resultGet = reader.ReadToEnd();
response.Close();
reader.Close();
return resultGet;