Try something like this.
System.Net.HttpWebRequest objRequest = (HttpWebRequest)WebRequest.Create("http://www.cybexexim.net/Downloads/" + strFilename);
request.ContentType = "application/json; charset=utf-8";
request.Credentials = CredentialCache.DefaultCredentials;
try
{
response = (HttpWebResponse)request.GetResponse();
}
catch(WebException ex)
{
continue;
}
if it still throws error, catch the error and let us know the error message.