Restrict each user to a single session in window server 2008 R2 or 2012
2014-10-31
In window server 2008 R2
In run, input 'tsconfig.msc' or menu 'Start'->Administrative Tools->Remote Desktop Services->Remote Desktop Session Host Configuration to open the configuration.
In pop up configuration, double click on 'Restrict each user to a single session' and unselect the option
In window server 2012
open ‘gpedit.msc‘, and go to the following location
Computer Configuration\Administrative Templates\Windows Components\Remote Desktop Services\Remote Desktop Session Host\Connections\