Your problem is finding a way for a logging program 
    to run anytime someone logs in. If you only want it 
    to run when the computer is rebooted, you could 
    reference your batch file in AUTOEXEC.BAT or 
    WINSTART.BAT. If you only want it to run when Windows 
    starts, you might add it to the "run=" line in WIN.INI 
    or put a shortcut to your batch file in the Startup 
    folder for every user. But if you want it to run for 
    every user (including new ones) at every login, you're 
    stuck going into the registry. Press the "Start" 
    button, select "Run...", type in regedit.exe, and 
    navigate your way to 
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    Select "Edit" / "New" / "String Value". Name it 
    whatever you want, and add the name of your batch 
    file for the value data.
    
    Now then... Here is the batch file I use for similar 
    things. I call it BOOTLOG.BAT

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call current.bat
echo Login occured at %date% %time% >> c:\bootlog.log
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    The call to CURRENT.BAT is used to set the time and 
    date into the environment. Here is what I use for CURRENT.BAT:

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:: This batch file MUST be named CURRENT.BAT
:: DATE is %4, TIME is %3
:: Current date is Thu 01-22-1998
:: Current time is  8:52:28.07a
if "%3"=="" goto GETDATE
if "%4"=="" goto SETTIME
goto SETDATE
:SETTIME
set TIME=%3
goto DONE
:SETDATE
set DATE=%4
goto DONE
:GETDATE
echo.|date>temp.bat
call temp.bat
echo.|time>temp.bat
call temp.bat
if exist temp.bat del temp.bat
goto DONE
:DONE
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