u_extend1 log file to Big

I seen this post and they ran this command:  Does anyone know where to do this?  I tried to set it up in Task manage in Windows SBS 2008.

I trim mine with the following command which creates a scheduled task to do it :-

at 12:00 /EVERY:Su Forfiles.exe -p C:\WINDOWS\system32\LogFiles\W3SVC1 -m *.log -d -30 -c \"Cmd.exe /C del @path\"

Thanks

Dennis Reist