Call a local C# webservice from ajax , 401 error Unauthorized

Question

I have a problem with a login function that is called by ajax , that's the code of the function it's a webservice visible

[WebMethod]
    [System.Web.Script.Services.ScriptMethod]
    public string CheckData(string login, string Pass)
    {
        global gb = new global();

        if (gb.CheckUserExist(login, Pass))
        {
            System.Web.Security.FormsAuthentication.RedirectFromLoginPage(login, true);
            HttpCookie cookie = new HttpCookie("userData",login);
            cookie.Expires = DateTime.Now.AddMonths(2);
            Mosab2aModel.Mosab2aEntities context = new Mosab2aModel.Mosab2aEntities();

            var User = context.Users.Where(x => x.UserName == login && x.Password == Pass)
                .Select(x => new { x.UserName, x.Password, x.Admin, x.DisplayName, x.FBID }).First();

            cookie["UserName"] = User.UserName;
            cookie["Password"] = User.Password;
            cookie["isAdmin"] = User.Admin.ToString();
            cookie["Name"] = User.DisplayName;
            cookie["FBID"] = User.FBID;
            Context.Response.Cookies.Add(cookie);
            //Context.Response.Redirect("/Default.aspx");
            return "1";
        }
        else
        {
            return "0";
        }
    }

I call it by ajax here

$.ajax({
                    type: "POST",
                    url: 'LoginService.asmx/CheckData',
                    data: "{'login':'"+ login +"','Pass':'"+pass +"'}",
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                        success: function(msg)
                        {

                            if (msg.d == "1")
                            {
                                //document.location.href = '/Default.aspx';
                            }
                            else
                            {
                                formWrapper.clearMessages();
                                displayError('Username or password is incorrect');
                            }
                        },
                        error: function()
                        {
                            formWrapper.clearMessages();
                            displayError('Error in contacting server , try again later.');
                        }
                  });

I have a strange problem if the user doesn't exist , the function works well and it return the value of 0 and the error diplays , but If the function found the user it get an 401 error Unauthorized.

edit: after several search the problem is with this line !

System.Web.Security.FormsAuthentication.RedirectFromLoginPage(login, true);

Answer 1

乍一看，似乎已通过身份验证的用户对ReturnURL（或默认URL）指定的页面没有适当的权限。

Answer 2

通过允许公共访问Web服务解决了问题，通过web.config运行安全模型时默认情况下拒绝该问题。谢谢。