WebClient call works in WinXP but not on Win7

Question

The following call returns a result in WinXP but not on Win7:

 using (WebClient client = new WebClient())
            {
                var result = client.DownloadString("https://secure.plimus.com/jsp/validateKey.jsp");
            }

I get "System.Net.WebException: The operation has timed out" exception

What is it that I'm doing wrong?

Answer 1

You should try to see if System.Net tracing can provide you more information on the connection attempt,

http://blogs.msdn.com/b/asiatech/archive/2009/04/08/using-system-net-trace-to-troubleshooting-ssl-problem-in-net-2-0-application.aspx

Better collect trace files from both Windows XP and Windows 7. Compare them and you will see the cause.