Hi Henrik

The owin startup class should look something like this:

using MyProject.Core;
using MyProject.Core.Filters;
using Hangfire;
using Hangfire.Server;
using Hangfire.Storage;
using Microsoft.AspNet.Identity;
using Microsoft.Owin;
using Microsoft.Owin.Security.Cookies;
using Owin;
using System;
using Umbraco.Web;

[assembly: OwinStartup(nameof(UmbracoStandardOwinStartup), typeof(UmbracoStandardOwinStartup))]
namespace MyProject.Core
{
    public class UmbracoStandardOwinStartup : UmbracoDefaultOwinStartup
    {
        public override void Configuration(IAppBuilder app)
        {
            // Ensure the default options are configured
            base.Configuration(app);

            app.UseCookieAuthentication(new CookieAuthenticationOptions
            {
                AuthenticationType = DefaultAuthenticationTypes.ApplicationCookie,
                LoginPath = new PathString("/")
            });

            try
            {
                var dashboardOptions = new DashboardOptions
                {
                    // Only grant access to users in Umbraco with access to the Hangfire Section
                    Authorization = new[] { new UmbracoAuthorizationFilter() },

                    // Avoid showing back to site link
                    AppPath = null
                };

                app.UseHangfireDashboard("/hangfire", dashboardOptions);
                app.UseHangfireServer();

                // Run Hangfire jobs
            }
            catch (InvalidOperationException ex)
            {
                // JobStorage.Current is not configured when installing updates
                if (!ex.Message.StartsWith("JobStorage.Current"))
                    throw;
            }
        }
    }
}

...

using Hangfire.Annotations;
using Hangfire.Dashboard;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Web;
using Umbraco.Web.Composing;
using Umbraco.Web.Security;

namespace MyProject.Core.Filters
{
    public class UmbracoAuthorizationFilter : IDashboardAuthorizationFilter
    {
        public bool Authorize([NotNull] DashboardContext context)
        {
            var http = new HttpContextWrapper(HttpContext.Current);
            var ticket = http.GetUmbracoAuthTicket();
            http.AuthenticateCurrentRequest(ticket, true);

            var user = Current.UmbracoContext.Security.CurrentUser;

            return user != null && user.Groups.Any(g => g.Alias == "admin");
        }
    }
}

Furthermore you need to ensure you have changed the default value of owin:appStartup key in web.config

<appSettings>
     ...
     <add key="owin:appStartup" value="UmbracoStandardOwinStartup" />
</appSettings>

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