In ADFS you need to create a Relying Party Trust. The following procedure uses ADFS 3.0 on Windows Server 2016 and shows demistodev.local as the ADFS portal service which will allow a trust connection from the https://demo.demisto.com web server.
You must have a valid and trusted server certificate for ADFS to work, not the self-signed certificates that come with Cortex XSOAR. If you do not use a trusted server certificate for ADFS, you will experience TLS connection issues with ADFS and the integration will not work properly.
Log in to the ADFS server management console.
In the tree in the left panel, right-click Service and select Edit Federation Service Properties.
Click the General tab and confirm that the DNS entries and certificates names are correct.
In the tree in the left panel, right-click Relying Party Trusts and select Add Relying Party Trusts.