JSI Tip 8768. How can I prevent users from logging on more than once, without using the Cconnect.exe Resource Kit Tool?

The Windows 2000 Server Resource Kit has the Cconnect.exe tool to prevent users from logging on more than once.

In tip 0296 » A better way to prevent a user from logging on more than once, I introduced a freeware solution that might work in your environment.

Using the PsShutdown.exe and PsLoggedOn.exe freeware, you can use the following code in your logon script to prevent a user from logging on more than once:

@echo off
setlocal ENABLEDELAYEDEXPANSION
:: Your normal logon script code here.

:: Duplicate logon code here
set DUP=N
:: Is the user logged on using this domain account on any other workstation?
for /f "Tokens=*" %%a in ('%LOGONSERVER%\NETLOGON\psloggedon.exe -L %UserName%^|FIND /I "%UserDomain%\%UserName%"^|FIND /I /V "%ComputerName%"') do (
 set DUP=%%a
:: The following 3 lines are optional. They send a message to the users other workstation.
 set DUP=!DUP:*logged onto =!
 set DUP=!DUP: locally.=!
 net send !DUP! You attempted to logon to %ComputerName%, but you were already logged onto !DUP!. Only one logon is allowed.
)
if "%DUP%" EQU "N" endlocal&goto :EOF
:: Log the user off this workstation.
%LOGONSERVER%\NETLOGON\psshutdown.exe -o

NOTE: See Microsoft releases LimitLogin v1.0.