Hello,

I have found the way, there is needed that Authentication cookie be manually created instead of SetAuthCookie:

    public static void Authenticate(string username, int memberGroupId)
    {
        FormsAuthenticationTicket ticket = new FormsAuthenticationTicket(1, 
                                                                         username, 
                                                                         DateTime.Now, 
                                                                         DateTime.Now.AddMinutes(FormsAuthentication.Timeout.Minutes), 
                                                                         false, 
                                                                         memberGroupId.ToString());

        HttpCookie cookie = new HttpCookie(FormsAuthentication.FormsCookieName);
        cookie.Value = FormsAuthentication.Encrypt(ticket);

        HttpContext.Current.Response.SetCookie(cookie);
    }

In this case, memberGroupId is stored in UserData property of FormsAuthenticationTicket object encrypted and sent to member.

In order to get memberGroupId from the cookie:

    public static Models.DocumentTypes.Core.MemberGroup CurrentMemberGroup
    {
        get
        {
            Models.DocumentTypes.Core.MemberGroup memberGroup = null;

            HttpCookie cookie = HttpContext.Current.Request.Cookies[FormsAuthentication.FormsCookieName];

            if (cookie != null)
            {
                FormsAuthenticationTicket ticket = FormsAuthentication.Decrypt(cookie.Value);

                if (ticket != null)
                {
                    string memberGroupIdStr = ticket.UserData;

                    if (!string.IsNullOrEmpty(memberGroupIdStr))
                    {
                        int memberGroupId = 0;

                        if (int.TryParse(memberGroupIdStr, out memberGroupId) && memberGroupId > 0)
                        {
                            UmbracoHelper helper = new UmbracoHelper(UmbracoContext.Current);
                            memberGroup = helper.TypedContent(memberGroupId) as Models.DocumentTypes.Core.MemberGroup;
                        }
                    }
                }
            }

            return memberGroup;
        }
    }

The point of this task is that after entering member's username and password, the member must choose a Member group defined in Content tree of Umbraco and Authenticated to the site.

This was challenge because the chosen MemberGroup cannot be stored in Session (Session - InProc), after restarting server, session is emtpy but member exists as authenticated on the site.

This could help, for similar tasks that someone gets.

Cheers

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