[keycloak-user] Kerberos Authentication

Hello Keycloak Users, I configured Kerberos in Keycloak (newest version) and all seems fine. When I activate it in the Authentication flow section the following error is shown on the login page: "Kerberos is not set up. You cannot login." There is no log entry or something else, nothing. I also searched for this message but no solution. It is not clear, why it is not working. Does anyone have an idea? Thanks