ASP.Net Core Identity - Unable to stay logged in for more than 20 mintues - IIS 7.5

Question

After deploying an ASP.Net Core app using Identity to Windows 2008 R2 (IIS 7.5) I cannot stay logged in after about 20 minutes of inactivity. I'm only using simple username / password authentication, no third party stuff.

This is not an issue on my Dev machine running VS 2017.

AccountController.cs

    public async Task<IActionResult> Login(LoginViewModel model, string returnUrl = null)
    {
        ViewData["ReturnUrl"] = returnUrl;
        if (ModelState.IsValid)
        {
            var result = await _signInManager.PasswordSignInAsync(model.Email, model.Password, true, lockoutOnFailure: false);
            if (result.Succeeded)
            {
                _logger.LogInformation(1, "User logged in.");
                return RedirectToLocal(returnUrl);
            }
            if (result.RequiresTwoFactor)
            {
                return RedirectToAction(nameof(SendCode), new { ReturnUrl = returnUrl, RememberMe = model.RememberMe });
            }
            if (result.IsLockedOut)
            {
                _logger.LogWarning(2, "User account locked out.");
                return View("Lockout");
            }
            else
            {
                ModelState.AddModelError(string.Empty, "Invalid login attempt.");
                return View(model);
            }
        }

        return View(model);
    }

Any help kindly appreciated.

EDIT Here is my ConfigureServices method in it's entirety. It has an authorization policy which could be relevant.

        public void ConfigureServices(IServiceCollection services)
    {
        // Add framework services.
        services.AddDbContext<ApplicationDbContext>(options =>
            options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));

        services.AddIdentity<ApplicationUser, ApplicationRole>()
            .AddEntityFrameworkStores<ApplicationDbContext>()
            .AddDefaultTokenProviders();


        services.AddAuthorization(options =>
        {
            options.AddPolicy("UserOnly", policy => policy.RequireRole("User"));
            options.AddPolicy("InstructorOnly", policy => policy.RequireRole("Instructor"));
            options.AddPolicy("AdminOnly", policy => policy.RequireRole("Admin"));
            options.AddPolicy("SystemManagerOnly", policy => policy.RequireRole("Manager"));

        });

        services.AddMvc(config =>
        {
            var policy = new AuthorizationPolicyBuilder()
                             .RequireAuthenticatedUser()
                             .Build();
            config.Filters.Add(new AuthorizeFilter(policy));
        });

        // Add application services.
        services.AddTransient<IEmailSender, AuthMessageSender>();
        services.AddTransient<ISmsSender, AuthMessageSender>();

        // Configure Identity
        services.Configure<IdentityOptions>(options =>
        {
            // Password settings
            options.Password.RequireDigit = true;
            options.Password.RequiredLength = 8;
            options.Password.RequireNonAlphanumeric = false;
            options.Password.RequireUppercase = false;
            options.Password.RequireLowercase = false;

            // Lockout settings
            options.Lockout.DefaultLockoutTimeSpan = TimeSpan.FromMinutes(240);
            options.Lockout.MaxFailedAccessAttempts = 10;

            // Cookie settings
            options.Cookies.ApplicationCookie.ExpireTimeSpan = TimeSpan.FromDays(15);
            options.Cookies.ApplicationCookie.LoginPath = "/Account/LogIn";
            options.Cookies.ApplicationCookie.LogoutPath = "/Account/LogOff";
            options.Cookies.ApplicationCookie.SlidingExpiration = true;

            // User settings
            options.User.RequireUniqueEmail = true;



        });

        var appSettings = Configuration.GetSection("AppSettings");
        services.Configure<AppSettings>(appSettings);

        // Inject the ability to get current user
        services.AddTransient<IHttpContextAccessor, HttpContextAccessor>();
        // Inject the User access class
        services.AddTransient<UserResolverService>();


    }

Here is a screenshot of Chrome Dev Tools showing the response/request cookie. The Login page seems to send the correct cookie with a an expiration 15 days into the future. Subsequent pages are called using this cookie.

Answer 1

For some very strange reason I'm not seeing this problem anymore.

The only change I made to either config or code was configuring the IIS version log to enable cs(Cookie).

Thank for your assistance @Rohith Rajan