ChangepasswordAsync not work
<p>I used this code for admin panel to changed password of customer by manager,I did not get any Error. but password not changed, 
i got my coed from <a href="https://stackoverflow.com/questions/29291366/asp-net-identity-change-password">this</a> </p>

<pre><code> [HttpPost]
    [ValidateAntiForgeryToken]
    public virtual  ActionResult ChangeUserPassword(SetPasswordViewModel model,string userId)
    {
        if (ModelState.IsValid)
        {
            //var result = await UserManager.AddPasswordAsync(User.Identity.GetUserId(), model.NewPassword);
            ApplicationUser appUser = db.Users.Find(userId);
            var result =  UserManager.ChangePasswordAsync(appUser, model.NewPassword);
           if (result.IsCompleted)
            {
                var user =  UserManager.FindById(User.Identity.GetUserId());
                //var user = db.Users.Find(userId);
                if (user != null)
                {
                    //await SignInManager&lt;,&gt;.SignInAsync(user, isPersistent: false, rememberBrowser: false);
                }
                return RedirectToAction("Index", new { Message = ManageController.ManageMessageId.SetPasswordSuccess });
            }
            // AddErrors(result);
        }

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

}
</code></pre>

<p>and in controller for change use this</p>

<pre><code> public async Task&lt;IdentityResult&gt; ChangePasswordAsync(ApplicationUser Appuser, string newPassword)
    {
        var store = this.Store as Microsoft.AspNet.Identity.IUserPasswordStore&lt;ApplicationUser,string&gt;;
        if (store == null)
        {
            var errors = new string[]
            {
            "Current UserStore doesn't implement IUserPasswordStore"
            };
            return IdentityResult.Failed(errors);
            // return Task.FromResult(new IdentityResult(errors) { Succeeded = false });

        }

        var newPasswordHash = this.PasswordHasher.HashPassword(newPassword);

        await store.SetPasswordHashAsync(Appuser, newPasswordHash);
        await store.UpdateAsync(Appuser);

        //return await Task.FromResult&lt;IdentityResult&gt;(IdentityResult.Success);
        return IdentityResult.Success;
    }
}
</code></pre>

<p>whats my mistake?</p>

<p>after update answer i use this method instead </p>

<pre><code> [HttpPost]
    public async Task&lt;IdentityResult&gt; ChangePasswordAsync(ApplicationUser appuserId, string newPassword)
    {
        ApplicationDbContext db = new ApplicationDbContext();
        //var userr =await db.Users.FirstOrDefaultAsync(x =&gt; x.Id == appuserId.Id);

        var newPasswordHash = this.PasswordHasher.HashPassword(newPassword);

        db.Entry(Users).State = EntityState.Modified;
        if (appuserId != null) appuserId.PasswordHash = newPasswordHash;
        db.SaveChanges();
        return IdentityResult.Success;
    }
</code></pre>

<p>but had the same problem again </p>

<p>in IdentityModels.cs i had</p>

<pre><code> public DbSet&lt;CommonAction&gt; CommonActions { get; set; }
    public DbSet&lt;PublicContent&gt; PublicContents { get; set; }
    public DbSet&lt;MainSubject&gt; MainSubjects { get; set; }
    public DbSet&lt;EducationLevel&gt; EducationLevels { get; set; }
    public DbSet&lt;TimePeriod&gt; TimePeriods { get; set; }
    public DbSet&lt;HelpType&gt; HelpTypes { get; set; }
    public DbSet&lt;FinancialSupport&gt; FinancialSupports { get; set; }
    public DbSet&lt;LinksStatistic&gt; LinksStatistics { get; set; }
    public DbSet&lt;SlideOfCommonAction&gt; SlideOfCommonActions { get; set; }
</code></pre>

<p>in normal model IdentityModel User is not register as DbSet 
()</p>