Hi all, 

As the title says, after upgrading the platform to 11.40.0, I am experiencing issues with SSO. We have Microsoft Entra configured. 

Currently, when I navigate to a Reactive Web Application that was republished after the upgrade, I receive the following error: “There was an error processing your request.” 

However, for applications that were not republished, I receive: “Unable to process requests” After this error, the application navigates to the Users module. 

When I try again for the application that was not republished, the login is successful, and navigation to all other applications works as expected as long as the session remains active. 

We are using the standard authentication logic as described in the OutSystems documentation. (see screenshot)

I also noticed the following error in Service Center: [ErrorScreen] The input is not a valid Base-64 string as it contains a non-base 64 character, more than two padding characters, or an illegal character among the padding characters. 

Initially, we assumed this might be related to applications that have an underscore (_) in the name, but after testing applications without any special characters, the same error still occurred. 

Does anyone have an idea what the issue might be, or where we should start investigating? 

Thanks in advance. 

Kind regards, 

Mert