my code is:

 protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                Editor1.SecurityPolicyFile = "default.config";
                string usersFolder = "~/Uploads/"+User.Identity.Name+"/";
                SetUsersFolder(usersFolder);
            }

       }

private void SetUsersFolder(string usersFolder)
        {
            string newFolder = Server.MapPath(usersFolder);
            System.IO.Directory.CreateDirectory(newFolder);
            Editor1.Setting["security:ImageGalleryPath"] = newFolder;
            Editor1.Setting["security:MediaGalleryPath"] = newFolder;
            Editor1.Setting["security:FlashGalleryPath"] = newFolder;
        }

this code is good in firefox,but in ie6 is bad!