Azure AD B2C: Api authentication error

Question

Hello,

I'm working with .Net 7 and Visual Studio 2022 in developing web api. I use Azure AD B2C for authentication. When I call my api I receive the error (in bold the part probably important):

System.InvalidOperationException: IDX20803: Unable to obtain configuration from: 'https://<My Tenant>.b2clogin.com/<My Tenant>.onmicrosoft.com/B2C_1_<My Acccess_Rule>/v2.0/.well-known/openid-configuration'. Will retry at '06/10/2023 16:08:19 +00:00'. Exception: 'System.TypeLoadException: Could not load type 'Microsoft.IdentityModel.Json.JsonConvert' from assembly 'Microsoft.IdentityModel.Tokens, Version=7.0.2.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'.
at Microsoft.IdentityModel.Protocols.OpenIdConnect.OpenIdConnectConfigurationRetriever.GetAsync(String address, IDocumentRetriever retriever, CancellationToken cancel)
at System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[TStateMachine]
at Microsoft.IdentityModel.Protocols.OpenIdConnect.OpenIdConnectConfigurationRetriever.GetAsync(String address, IDocumentRetriever retriever, CancellationToken cancel)
at Microsoft.IdentityModel.Protocols.OpenIdConnect.OpenIdConnectConfigurationRetriever.Microsoft.IdentityModel.Protocols.IConfigurationRetriever<Microsoft.IdentityModel.Protocols.OpenIdConnect.OpenIdConnectConfiguration>.GetConfigurationAsync(String address, IDocumentRetriever retriever, CancellationToken cancel)
at Microsoft.IdentityModel.Protocols.ConfigurationManager1.GetConfigurationAsync(CancellationToken cancel)'. ---> System.TypeLoadException: Could not load type 'Microsoft.IdentityModel.Json.JsonConvert' from assembly 'Microsoft.IdentityModel.Tokens, Version=7.0.2.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'. at Microsoft.IdentityModel.Protocols.OpenIdConnect.OpenIdConnectConfigurationRetriever.GetAsync(String address, IDocumentRetriever retriever, CancellationToken cancel) at System.Runtime.CompilerServices.AsyncMethodBuilderCore.StartTStateMachine at Microsoft.IdentityModel.Protocols.OpenIdConnect.OpenIdConnectConfigurationRetriever.GetAsync(String address, IDocumentRetriever retriever, CancellationToken cancel) at Microsoft.IdentityModel.Protocols.OpenIdConnect.OpenIdConnectConfigurationRetriever.Microsoft.IdentityModel.Protocols.IConfigurationRetriever<Microsoft.IdentityModel.Protocols.OpenIdConnect.OpenIdConnectConfiguration>.GetConfigurationAsync(String address, IDocumentRetriever retriever, CancellationToken cancel) at Microsoft.IdentityModel.Protocols.ConfigurationManager1.GetConfigurationAsync(CancellationToken cancel)
--- End of inner exception stack trace ---
at Microsoft.IdentityModel.Protocols.ConfigurationManager1.GetConfigurationAsync(CancellationToken cancel) at Microsoft.AspNetCore.Authentication.JwtBearer.JwtBearerHandler.HandleAuthenticateAsync() at Microsoft.AspNetCore.Authentication.JwtBearer.JwtBearerHandler.HandleAuthenticateAsync() at Microsoft.AspNetCore.Authentication.AuthenticationHandler1.AuthenticateAsync()
at Microsoft.AspNetCore.Authentication.AuthenticationService.AuthenticateAsync(HttpContext context, String scheme)
at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
at Swashbuckle.AspNetCore.SwaggerUI.SwaggerUIMiddleware.Invoke(HttpContext httpContext)
at Swashbuckle.AspNetCore.Swagger.SwaggerMiddleware.Invoke(HttpContext httpContext, ISwaggerProvider swaggerProvider)
at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddlewareImpl.Invoke(HttpContext context) HEADERS======= Accept: /
Host: localhost:39002
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/117.0.0.0 Safari/537.36
Accept-Encoding: gzip, deflate, br
Accept-Language: it-IT,it;q=0.9,en-US;q=0.8,en;q=0.7
Authorization: Bearer <token>
Origin: [http://localhost:6420]
Referer: [http://localhost:6420/]
sec-ch-ua: "Google Chrome";v="117", "Not;A=Brand";v="8", "Chromium";v="117"
sec-ch-ua-mobile: ?0
sec-ch-ua-platform: "Windows"
sec-fetch-site: cross-site
sec-fetch-mode: cors
sec-fetch-dest: empty  

Thanks for any help

Answer 1

Hi @Lorenzo Soncini ,

Thanks for reaching out.

It seems that you are facing an issue with obtaining configuration from the provided URL. The error message indicates that the type 'Microsoft.IdentityModel.Json.JsonConvert' could not be loaded from the assembly 'Microsoft.IdentityModel.Tokens'. This could be due to a version mismatch between the Microsoft.IdentityModel.Tokens assembly and the Microsoft.IdentityModel.Json assembly.

To resolve this issue, you can try updating the Microsoft.IdentityModel.Protocols.OpenIdConnect assembly to the latest version and ensure that the Microsoft.IdentityModel.Json assembly is also updated to the same version. You can also try cleaning and rebuilding your project to ensure that all the dependencies are up to date.

dotnet add package Microsoft.IdentityModel.Protocols.OpenIdConnect --version 7.0.2

Reference: https://www.nuget.org/packages/Microsoft.IdentityModel.Protocols.OpenIdConnect/

https://github.com/AzureAD/azure-activedirectory-identitymodel-extensions-for-dotnet/wiki/IdentityModel-7x

Thanks,

Shweta