Sample UserManager

UserManager.cs

public class UserManager : UserManager<User>
{
    public UserManager(IUserStore<User> store)
        : base(store)
    {
    }

    // This method is called by Owin therefore best place to configure your User Manager
    public static UserManager Create(
        IdentityFactoryOptions<UserManager> options, IOwinContext context)
    {
        var manager = new UserManager(
            new UserStore<User>(context.Get<TimesheetsContext>()));

        // Configure your manager ...

        return manager;
    }
}