Got Invalid_client error using Azure B2C as Identity Provider in the OpenId SSO

Hey Guillaume, can you share a bit more about how you've set up the OIDC configuration form and where you're getting this error?

We've checked on our side and we're seeing some errors, but none of them specific to an “invalid_client” error interestingly enough. Here's what we're seeing:

• “server response missing access token”: After what looks like a successful user sign in, token exchange failed because we got an empty access token. 
• "invalid_request": which seems to happen when a user clicks the forgotten password link, not sure but this seems like a configuration setup on your end that needs to be handled. 
• “error processing request - Missing cookie data”: also not sure what this is regarding but seems to be cookie related. 

The team is thinking the issue you're having is related to the missing access token. There's a setting inside Entra's OIDC configuration for this (I'm attaching a screenshot of the page). Can you confirm that the “Access tokens” checkbox is selected? 

Then I'm afraid we've exhausted the possibilities that it's something on our end that's causing the error, we're still not seeing it in our error logs. I tried looking around Azure's documentation for the “invalid_error” message and I see it referenced here in their error codes.