exchange  环境正常，能正常收发邮件
但是，尝试用webdav  与exchange 通信的时候，报了一个错误：未找到提供程序。该程序可能未正确安装
找了半天不知道哪里出错了

 public static void TestGetMail()
        {
            ADODB.Connection oCn = null;
            ADODB.Recordset oRs = null;
            ADODB.Fields oFields = null;
            ADODB.Field oField = null;
 
 
            string sFdUrl = "http://192.168.253.193/exchange/Administrator/收件";
            try
            {
                oCn = new ADODB.Connection();
                oRs = new ADODB.Recordset();
                oCn.Provider = "exoledb.datasource";
                oCn.Open(sFdUrl, "administrator", "1qaz2WSX", -1);//error  : 未找到提供程序。该程序可能未正确安装
                string strSql;
                strSql = "";
                strSql = "select ";
                strSql = strSql + " \"urn:schemas:mailheader:content-class\"";
                strSql = strSql + ", \"DAV:href\" ";
                strSql = strSql + ", \"" + SqlFieldName.DisplayName + "\"";
                strSql = strSql + ", \"" + SqlFieldName.MId + "\"";
                strSql = strSql + ", \"" + SqlFieldName.Subject + "\"";
                strSql = strSql + " from scope ('shallow traversal of " + "\"";
                strSql = strSql + sFdUrl + "\"') ";
                strSql = strSql + " WHERE \"DAV:ishidden\" = false";
                strSql = strSql + " AND \"DAV:isfolder\" = false";
 
 
                oRs.Open(strSql, oCn,
                    ADODB.CursorTypeEnum.adOpenUnspecified,
                    ADODB.LockTypeEnum.adLockOptimistic, 1);
                Console.WriteLine(3);
                if (!oRs.EOF)
                {
                    oRs.MoveFirst();
                }
 
            }
            catch (Exception e)
            {
                Console.WriteLine("出错了");
                WriteLog(e.ToString());
            }
 
            Console.ReadKey();
 
        }

 exoledb.datasource  这个东西 不支持 远程调用，需要将 程序部署到exhcanserver上去