W2000 is, as far as I know going to be supported by Microsoft until at least 2011, so it is still worthwhile to keep as an operating system (I still run it on one of my desktops). I would suggest you either stay with NAV2006 & just subscribne to a further year of virus updates. Alternatively, & something I did a while back, you could dispense with NAV 2006 & use something like AVG, Bitdefender, Kapersky. I think you will find a vast improvement over NAV 2006. Most of Nortons products are now resource hogs.