I need ability to change password for user by admin. So, admin should not enter a current password of user, he should have ability to set a new password. I look at ChangePasswordAsync method, but this method requires to enter old password. So, this method is not appropriate for this task. Therefore I have made it by the following way:

        [HttpPost]
        public async Task&lt;ActionResult&gt; ChangePassword(ViewModels.Admin.ChangePasswordViewModel model)
        {
            var userManager = HttpContext.GetOwinContext().GetUserManager&lt;ApplicationUserManager&gt;();
            var result = await userManager.RemovePasswordAsync(model.UserId);
            if (result.Succeeded)
            {
                result = await userManager.AddPasswordAsync(model.UserId, model.Password);
                if (result.Succeeded)
                {
                    return RedirectToAction(&quot;UserList&quot;);
                }
                else
                {
                    ModelState.AddModelError(&quot;&quot;, result.Errors.FirstOrDefault());
                }
            }
            else
            {
                ModelState.AddModelError(&quot;&quot;, result.Errors.FirstOrDefault());
            }
            return View(model);
        }

it works, but theoretically we can receive error on AddPasswordAsync method. So, old password will be removed but new is not set. It&#39;s not good. Any way to do it in &quot;one transaction&quot;?
PS. I seen ResetPasswordAsync method with reset token, seems, it&#39;s more safe (because can&#39;t be unstable situation with user) but in any case, it does by 2 actions. 

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ASP.NET Identity change password