A Windows Server 2003 terminal server, in Remote Administration mode, can have two remote sessions, and one console session, for a total of three active sessions.
To limit Windows Server 2003 Terminal Services to one console session:
01. Start / Administrative Tools / Terminal Services Configuration.
02. Press Connections in the console tree.
03. Right-click RDP-Tcp, in the right-hand pane, and press Properties.
04. Select the Network Adapter tab.
05. Select 1 from the Maximum connections drop-down.
06. Select the Permissions tab.
07. Press Add.
08. Type Everyone into the Enter the object names to select (examples) box, and press Check Name.
09. Press OK.
10. Select the Everyone group in the Group or user names area and check the Deny box for Guest Access in the Permissions for Everyone area.
11. Press Apply and OK.
NOTE: To connect to session 0, use Windows XP, or Windows Server 2003, to run mstsc.exe /console.