This overrides and takes precedence over the settings specified in Terminal Services Configuration.
Open the Group Policy Object Editor snap-in.
Navigate through Computer Configuration --> Administrative Templates --> Windows Components in the tree in the left pane.
Select Terminal Services, and in the right pane, double-click the Limit Number of Connections setting.
Click Enabled.
Move to the "TS Maximum Connections allowed" box. In it, enter the maximum number of connections you want to allow, and then click OK.