However for some reasons you might want to be able to remotely log off the connected user if someone tries to open a new session with the same account. This is possible by using Group Policy. Click on the start menu, and execute "gpedit.msc", or click on the Group Policies in the Admin Tool under "server administration tab" as shown above.
Warning : Group Policy are not available on Home/Family/Basic version of Windows.
Then locate and enable the following GPO :
Computer Configuration\Administrative Templates\Windows Components\Remote Desktop Services\Remote Desktop Session Host\Connections\Restrict Remote Desktop Services users to a single Remote Desktop services session.
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