Web Client timeout while downloading photos from external link

I am trying to download 10 photos from an external link e.g http://images.net/images/20159178574IMG_0843.jpg

I am reading a text file on my drive and putting it on a list here is the code

List < string > lines = new List < string > ();
using(StreamReader r = new StreamReader(fileName)) 
{
    string line;
    while ((line = r.ReadLine()) != null) 
    {
        lines.Add(line);
    }
}

foreach(string s in lines) 
{
    getthefile(s, System.DateTime.Now.Hour + System.DateTime.Now.Minute + System.DateTime.Now.Second + ".jpg");
}

private void getthefile(string filename, string filenamesave) 
{
    if (checkurl(filename)) 
    {

        string filepath = @
        "D:\files" + "\\Photos\\" + filenamesave;
        WebClient webClient = new WebClient();
        webClient.DownloadFile(filename, filepath);
    }
}

private bool checkurl(string url) 
{
    var request = (HttpWebRequest) WebRequest.Create(url);
    request.Method = "HEAD";
    var response = (HttpWebResponse) request.GetResponse();

    switch ((int) response.StatusCode) 
    {
        case 200:
            return true;
        default:
            return false;
    }
}

Now the first photo on the list gets downloaded but when the loop moves to the next photo it gets stuck for about 2 minutes and throws a timeout exception I tried making a new list to see if it the error occurs again but sadly it throws the same error.

is there something wrong with my code or the server hosting the IIS?

thank you