Other 4xx codes
All HTTP status codes in ASP.NET Core
4xx Client error
419 Authentication Timeout
Not a standard code. StatusCodes has a constant for it; some frameworks use it for an expired session or CSRF token.
In ASP.NET Core: Use 401 instead.
419 in .NET
The StatusCodes constant, HttpStatusCode enum name, reason phrase, class, and how EnsureSuccessStatusCode() and the standard resilience handler treat 419.
| Constant | StatusCodes.Status419AuthenticationTimeout |
|---|---|
| HttpStatusCode | none; use (HttpStatusCode)419 |
| Reason phrase | Kestrel sends Authentication Timeout; HttpClient's ReasonPhrase is null |
| Class | 4xx, client error |
| IsSuccessStatusCode | false |
| EnsureSuccessStatusCode() | throws HttpRequestException: Response status code does not indicate success: 419. |
| Standard resilience handler | does not retry it |
Returning 419
Minimal APIs
Results.StatusCode(StatusCodes.Status419AuthenticationTimeout)
Results.Problem(statusCode: StatusCodes.Status419AuthenticationTimeout, detail: "...")Controllers
StatusCode(StatusCodes.Status419AuthenticationTimeout)
Problem(statusCode: StatusCodes.Status419AuthenticationTimeout, detail: "...")The ProblemDetails body
What Results.Problem(statusCode: 419) sends (with AddProblemDetails()), as application/problem+json:
{
"title": "Authentication Timeout",
"status": 419,
"traceId": "0HNA1B2C3D4E5:00000001"
}A controller's Problem(statusCode: 419) sends a different body, because MVC only fills type and title for codes in ApiBehaviorOptions.ClientErrorMapping:
{
"status": 419,
"traceId": "0HNA1B2C3D4E5:00000001"
}A bare StatusCode(419) in an [ApiController] also gets a ProblemDetails body automatically; Results.StatusCode(419) in a minimal API sends an empty body unless you add UseStatusCodePages().
Every response on this page was recorded from ASP.NET Core 10.0.12 on Kestrel in the Production environment; the HttpClient rows come from .NET 10.0.12 and Microsoft.Extensions.Http.Resilience 10.10.0.