We have a RAS GW that works really well for most users. They simply logon with username@ad_domain and can access apps etc all OK. The RAS GW does not run on the RDSH's and sits in front. We have some users that have a different UPN, they login with username@public_domain.com These users can login to the HTML5 HTML all OK, they can see the apps list etc. however, when they execute an app an error appears that the username was not found. We cannot see any errors in logs, the only error we see is in the Security Log on the RDSH, showing that the Microsoft Cryptography could not find the user. We can manually (via remote desktop client) connect to the RDSH with the users UPN as listed above and they can login and access the RDSH directly. It is only when the session goes through the RAS GW that the error appears. Any thoughts? Version 16.5.1