what KeepAlive property with Httpversion 11 true or false?

Question

Dear all,

                 I'm using Httpwebrequset method and ProtocolVersion 11 after thar error raised

'The underlying connection was closed: A connection that was expected to be kept alive was close by server '            how to resolved this issue

 

code here

HttpWebRequest req = (HttpWebRequest)(HttpWebRequest.Create(url));

req.Method = "POST";

req.ProtocolVersion = HttpVersion.Version11;

req.ContentType = "application/xml";

req.KeepAlive = false;req.Headers.Set(HttpRequestHeader.Authorization, "Basic   jhfgshfghj==");

// d1 = DateTime.Now;

XmlDocument XDAuth = new XmlDocument();

XmlNode docNode = XDAuth.CreateXmlDeclaration("1.0", "UTF-8", "yes");

XDAuth.AppendChild(docNode);

XmlNode Root = XDAuth.AppendChild(XDAuth.CreateElement("xml"));