Azure B2C invalid_instance

[cheoalfredo]

Core Library

MSAL.js (@azure/msal-browser)

Core Library Version

4.8.0

Wrapper Library

MSAL Angular (@azure/msal-angular)

Wrapper Library Version

4.0.7

Public or Confidential Client?

Public

Description

when setting msaljs for an angular standalone app for azure B2C, i set the authority to "https://tenant.b2clogin.com/tenant.onmicrosoft.com/policy/" and i keep getting the following error :

msal.js.browser@3.28.1 : Warning - A CloudInstanceDiscoveryErrorResponse was returned. The cloud instance discovery network request's status code is: 400

msal.js.browser@3.28.1 : Error - The CloudInstanceDiscoveryErrorResponse error is invalid_instance.

and the respective 400 from the get to the endpoint discovery

https://login.microsoftonline.com/common/discovery/instance?api-version=1.1&authorization_endpoint=https://xxxx.b2clogin.com/xxxx.onmicrosoft.com/b2c_xxxx/oauth2/v2.0/authorize

i tried using the authority with the format "https://instance/tfp/tenant/policy" as per recommedation in PublicClientApplication.ts and it does not work either.

please help, i also tried v3 and v4 in an standalone app (angular19) and the same issue

Error Message

msal.js.browser@3.28.1 : Warning - A CloudInstanceDiscoveryErrorResponse was returned. The cloud instance discovery network request's status code is: 400

msal.js.browser@3.28.1 : Error - The CloudInstanceDiscoveryErrorResponse error is invalid_instance.

MSAL Logs

No response

Network Trace (Preferrably Fiddler)

• Sent
• Pending

MSAL Configuration

{ 
  auth: {
        clientId: '<client_id>',
        authority: 'https://<tenant>.b2clogin.com/<tenant>.onmicrosoft.com/B2C_mypol',
        knownAuthorities: ['<tenant>.b2clogin.com'],
      },
}

Relevant Code Snippets

loginRedirect() {
    if (this.msalGuardConfig.authRequest) {
      this.authService.loginRedirect({
        ...this.msalGuardConfig.authRequest,
      } as RedirectRequest);
    } else {
      this.authService.loginRedirect();
    }
  }

Reproduction Steps

1. setup msaljs according to documentation (sample) in https://github.com/AzureAD/microsoft-authentication-library-for-js/tree/dev/samples/msal-angular-samples/angular-standalone-sample
2. set authority, clientid and knownAuthorities for msalConfig
3. Run the app

Expected Behavior

navigate ti azure bc2 to login the user

Identity Provider

Azure B2C Basic Policy

Browsers Affected (Select all that apply)

Chrome, Firefox, Edge

Regression

No response

[tnorling]

If it's attempting instance discovery it means knownAuthorities either isn't provided or doesn't match the authority passed in. Double check that knownAuthorities is in fact being passed in and matches.

[cheoalfredo]

@tnorling checked that, it's a match

[tnorling]

Can you please link us to a minimal repro?