WebClient myWebClient = new WebClient();
            myWebClient.Credentials = CredentialCache.DefaultCredentials;
            FileStream fs = new FileStream("C:\\NNN+2013711634041++正文.doc", FileMode.Open, FileAccess.Read);//本地磁盘文件
            BinaryReader r = new BinaryReader(fs);
            byte[] postArray = r.ReadBytes((int)fs.Length);
            Stream postStream = myWebClient.OpenWrite("D:\\FtpRoot", "PUT");//服务器指定目录
            postStream.Write(postArray, 0, postArray.Length);
            postStream.Close();
            fs.Dispose();在执行Stream postStream = myWebClient.OpenWrite("D:\\FtpRoot", "PUT");
这段代码的时候,提示D:\FtpRoot没权限,是为什么呢?