Horizon supports at most one desktop session and one application session per user on an RDS host. You must configure the RDS host to restrict users to a single session. For Windows Server 2012 R2, Windows Server 2016, or Windows Server 2019, you can restrict users to a single session in a group policy setting.
- In the folder Computer Configuration\Administrative Templates\Windows Components\Remote Desktop Services\Remote Desktop Session Host\Connections, Click .
- Enable the group policy setting Restrict Remote Desktop Services users to a single Remote Desktop Services session.