This new switch has several interesting features. The connections made with /admin switch don't count toward the terminal server session limits. In addition, if you use "mstsc /admin" to establish a remote desktop connection, you do not utilize Terminal Services client access license (CAL).

Another feature of /admin switch is that if you have administrative access and have the ability to use the /admin switch, you will be allowed to establish a remote desktop connection even if your permissions are set to Deny User Permissions To Log On To Terminal Server.

If you usually prefer to connect to the remote computer's console, you can modify the properties of the shortcut and add the /admin switch (%systemroot%\system32\mstsc.exe /admin.)