Some time ago, I was wrestling with getting an OCS inventory installer package made up and eventually gave up. Instead, I wrote a simple batch file that is called during the login batch file. The scan is quick enough for most people when they reboot and log in and you need not worry about installing anything on Windows PCs at all. Quite nice really. If the scan were too slow, I would write some additional batch code that would run the scan every 3-5 logins instead of every login but that hasn't been shown to be necessary at all.