Startup.cs

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

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

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

    services.AddMvc();

    // configure identity server with in-memory stores, keys, clients and scopes
    services.AddIdentityServer()
        .AddDeveloperSigningCredential()
        .AddInMemoryPersistedGrants()
        .AddInMemoryIdentityResources(Config.GetIdentityResources())
        .AddInMemoryApiResources(Config.GetApiResources())
        .AddInMemoryClients(Config.GetClients())
        .AddAspNetIdentity<ApplicationUser>()
        .AddProfileService<ProfileService>();
}