Windows authentication fail with "401 Unauthorized" - asp.net-core

Question

I have a MVC client accessing a Web API protected by IDS4. They all run on my local machine and hosted by IIS. The app works fine when using local identity for authentication. But when I try to use Windows authentication, I keep getting "401 Unauthorized" error from the dev tool and the login box keeps coming back to the browser.
Here is the Windows Authentication IIS setting
and enabled providers
It's almost like that the user ID or password was wrong, but that's nearly impossible because that's the domain user ID and password I use for logging into the system all the time. Besides, according to my reading, Windows Authentication is supposed to be "automatic", which means I will be authenticated silently without a login box in the first place.
Update
I enabled the IIS request tracing and here is the result from the log:
As you can see from the trace log item #29, the authentication (with the user ID I typed in, "DOM\Jack.Backer") was successful. However, some authorization item (#48) failed after that. And here is the detail of the failed item:
What's interesting is that the ErrorCode says that the operation (whatever it is) completed successfully, but still I received a warning with a HttpStatus=401 and a HttpReason=Unauthorized. Apparently, this is what failed my Windows Authentication. But what is this authorization about and how do I fix it?

Answer 1

In case anyone interested - I finally figured this one out. It is because the code that I downloaded from IndentityServer4's quickstart site in late 2020 doesn't have some of the important pieces needed for Windows authentication. Here is what I had to add to the Challenge function of the ExternalController class
and here is the ProcessWindowsLoginAsync function
private async Task<IActionResult> ProcessWindowsLoginAsync(string returnUrl)
{
var result = await HttpContext.AuthenticateAsync(AccountOptions.WindowsAuthenticationSchemeName);
if (result?.Principal is WindowsPrincipal wp)
{
var props = new AuthenticationProperties()
{
RedirectUri = Url.Action(nameof(Callback)),
Items =
{
{ "returnUrl", returnUrl },
{ "scheme", AccountOptions.WindowsAuthenticationSchemeName },
}
};
var id = new ClaimsIdentity(AccountOptions.WindowsAuthenticationSchemeName);
id.AddClaim(new Claim(JwtClaimTypes.Subject, wp.Identity.Name));
id.AddClaim(new Claim(JwtClaimTypes.Name, wp.Identity.Name));
if (AccountOptions.IncludeWindowsGroups)
{
var wi = wp.Identity as WindowsIdentity;
var groups = wi.Groups.Translate(typeof(NTAccount));
var roles = groups.Select(x => new Claim(JwtClaimTypes.Role, x.Value));
id.AddClaims(roles);
}
await HttpContext.SignInAsync(IdentityConstants.ExternalScheme, new ClaimsPrincipal(id), props);
return Redirect(props.RedirectUri);
}
else
{
return Challenge(AccountOptions.WindowsAuthenticationSchemeName);
}
}
Now my windows authentication works with no issues.