无法检查模型兼容性，因为DbContext实例不是使用Code First模式创建的

Question

客户给了我一个基于EF数据库优先（EDMX）开发的MVC项目。 它正在使用Asp.Net Identity，并且似乎在“代码优先”中。 我得到以下错误：

无法检查模型兼容性，因为DbContext实例不是使用Code First模式创建的。 无法检查从ObjectContext或使用EDMX文件创建的DbContext实例的兼容性。

它在一行上var user = await UserManager.FindByNameAsync(userName);

还有可能在Database First上有一个项目，并且在Code First上有Asp.Net Identity，或者我缺少什么吗？

下面是控制器代码：

public async Task<ActionResult> ForgotPassword(ForgotPasswordViewModel model)
{
    if (ModelState.IsValid)
    {
        var user = await UserManager.FindByNameAsync(model.Email);
        if (user == null || !(await UserManager.IsEmailConfirmedAsync(user.Id)))
        {
            // Don't reveal that the user does not exist or is not confirmed
            return View("ForgotPasswordConfirmation");
        }

        var code = await UserManager.GeneratePasswordResetTokenAsync(user.Id);
        var callbackUrl = Url.Action("ResetPassword", "Account", new { userId = user.Id, code = code }, protocol: Request.Url.Scheme);
        await UserManager.SendEmailAsync(user.Id, "Reset Password", "Please reset your password by clicking here: <a href=\"" + callbackUrl + "\">link</a>");
        ViewBag.Link = callbackUrl;
        return View("ForgotPasswordConfirmation");
    }

    // If we got this far, something failed, redisplay form
    return View(model);
}

下面是模型代码：

public virtual DbSet<User> Users { get; set; }

下面是Identity DbContex对象声明。

public class ApplicationDbContext : IdentityDbContext<User>
{
    public ApplicationDbContext()
        : base("EcoEntities", throwIfV1Schema: false)
    {
    }

    static ApplicationDbContext()
    {
        // Set the database intializer which is run once during application start
        // This seeds the database with admin user credentials and admin role
        Database.SetInitializer<ApplicationDbContext>(new ApplicationDbInitializer());
    }

    public static ApplicationDbContext Create()
    {
        return new ApplicationDbContext();
    }

    protected override void OnModelCreating(System.Data.Entity.DbModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        modelBuilder.Entity<User>().ToTable("User").Property(p=>p.Id).HasColumnName("UserId");
        modelBuilder.Entity<IdentityUserRole>().ToTable("UserRole");
        modelBuilder.Entity<IdentityUserLogin>().ToTable("UserLogin");
        modelBuilder.Entity<IdentityUserClaim>().ToTable("UserClaim");
        modelBuilder.Entity<IdentityRole>().ToTable("Roles").Property(p => p.Id).HasColumnName("RoleId");

        //System.Data.Entity.Database.SetInitializer<ApplicationDbContext>(null);
    }

}


public class ApplicationDbInitializer : DropCreateDatabaseIfModelChanges<ApplicationDbContext> 
{
    protected override void Seed(ApplicationDbContext context) {
        InitializeIdentityForEF(context);
        base.Seed(context);
    }

    //Create User=xxx with password=xxxxx in the Admin role        
    public static void InitializeIdentityForEF(ApplicationDbContext db) {
        var userManager = HttpContext.Current.GetOwinContext().GetUserManager<ApplicationUserManager>();
        var roleManager = HttpContext.Current.GetOwinContext().Get<ApplicationRoleManager>();
        const string name = "xxxx";
        const string password = "xxxx";
        const string roleName = "xxxx";

        //Create Role Admin if it does not exist
        var role = roleManager.FindByName(roleName);
        if (role == null) {
            role = new IdentityRole(roleName);
            var roleresult = roleManager.Create(role);
        }

        var user = userManager.FindByName(name);
        if (user == null) {
            user = new User { UserName = name, Email = name };
            var result = userManager.Create(user, password);
            result = userManager.SetLockoutEnabled(user.Id, false);
        }

        // Add user admin to Role Admin if not already added
        var rolesForUser = userManager.GetRoles(user.Id);
        if (!rolesForUser.Contains(role.Name)) {
            var result = userManager.AddToRole(user.Id, role.Name);
        }
    }
}