I'm trying to insert new items through the /base/feeds/items feed. I'm giving a web request to http://www.google.com/base/feeds/items, but in response I'm getting the above error. I'm giving my code snippet below, Can anybody help me out for this problem. Thanks in advance.

******************************************************************************************* HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http:// www.google.com/base/feeds/items");

request.Method = "POST";

WebProxy proxyObj = new WebProxy("http://192.168.10.90/GoogleBase"); request.Proxy = proxyObj;

request.ContentType = "application/atom+xml";

request.Headers.Add("Authorization", "AuthSub token=" + _token);

request.Headers.Add("X-Google-Key", "key=" + DevKey);

postData = "<?xml version='1.0'?>" +

"<entry xmlns='http://www.w3.org/2005/Atom' xmlns:g='http:// base.google.com/ns/1.0'>"+

"<g:item_type>vehicles</g:item_type>"+ "<author>"+ "<name> Autoexact </name>"+ "<email> auto...@gmail.com </email>"+ "</author>"+ "<title> Offers from autoexact </title>"+ "<content> Description of the Offer </content>"+ "<g:color> silver </g:color>"+ "<g:condition> used </g:condition>"+ "<g:location> cincinnati oh us </g:location>"+ "<g:make> Audi </g:make>"+ "<g:mileage> 25 </g:mileage>"+ "<g:model> 325-A </g:model>"+ "<g:price> 25034.0 usd </g:price>"+ "<g:vehicle_type> 4 DOOR </g:vehicle_type>"+ "<g:vin> 3GCEC14X26G154689 </g:vin>"+ "<g:year> 2007 </g:year>"+ "</entry>";

byte[] byteArray = Encoding.UTF8.GetBytes(postData);

try { Stream dataStream = request.GetRequestStream(); dataStream.Write(byteArray , 0 , byteArray.Length); dataStream.Close(); HttpWebResponse response = (HttpWebResponse)request.GetResponse(); Stream outputStream = response.GetResponseStream(); StreamReader reader = new StreamReader(outputStream); } catch(WebException eX) { this.errMsg.Text = eX.ToString(); }

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