Hi all

I am trying to execute a WebDAV query against a webmail Exchange inbox using XMLHttp but I keep getting an error stating "The handle is invalid" when I call the send() method.

My code is as follows:

Code:
MSXML2.ServerXMLHTTP40Class xmlHttp = new ServerXMLHTTP40Class();
string folderQuery = "<?xml version=\"1.0\"?>" + 
   "<g:searchrequest xmlns:g=\"DAV:\">" + 
   "<g:sql>SELECT TOP 1 \"urn:schemas:httpmail:subject\", " + 
   "\"urn:schemas:httpmail:from\", \"DAV:displayname\", "  +
   "\"urn:schemas:httpmail:textdescription\" " + 
   "FROM SCOPE('shallow traversal of \"" + serverUrl + "\"') "  + 
   "WHERE \"DAV:ishidden\" = False AND \"DAV:isfolder\" = False "  +
   "AND \"urn:schemas:httpmail:subject\" LIKE '%" + "Undeliverable" + 
   "%' " + "ORDER BY \"urn:schemas:httpmail:date\" DESC"  + 
   "</g:sql></g:searchrequest>";

// Open a connection to the exchange server.
xmlHttp.open("PROPFIND", serverUrl, false, userName, password);
// Send the request.
xmlHttp.setRequestHeader("SQL", folderQuery);
xmlHttp.setRequestHeader("Content-type", "text/xml");
xmlHttp.setRequestHeader("Depth", "1");
xmlHttp.send(null);
I've tried browsing to the URL in IE and I can access the inbox with the username and password.

Can anyone help me with this, please?

Thanks as always