"Unable to connect to server" error while attempt to get address by entering latitude and longitude

public string GetLocation() 
{
    HttpWebRequest request = default(HttpWebRequest);
    HttpWebResponse response = null;
    StreamReader reader = default(StreamReader);
    string json = null;
    try 
    {
        //Create the web request   
        request = (HttpWebRequest)WebRequest.Create("http://maps.googleapis.com/maps/api/geocode/json?latlng=27.7121753,85.3434027&sensor=true");
         //Get response   
            response = (HttpWebResponse)request.GetResponse();           
        //Get the response stream into a reader   
            reader = new StreamReader(response.GetResponseStream());
            json = reader.ReadToEnd();
            response.Close();
            TextBox1.Text = json;
            if (json.Contains("ZERO_RESULTS"))
            {
                TextBox2.Text = "No Address Available";
            };

            if (json.Contains("formatted_address"))
            {
                //CurrentAddress.Text = "Address Available";
                int start = json.IndexOf("formatted_address");
                int end = json.IndexOf(", Nepal");
                string AddStart = json.Substring(start + 21);
                string EndStart = json.Substring(end);
                string FinalAddress = AddStart.Replace(EndStart, ""); //Gives Full Address, One Line

                TextBox2.Text = FinalAddress;

            };
    }
    catch (Exception ex)
    {
        string Message = "Error: " + ex.ToString();
    }
}

"Unable to connect to the remote server"..