NOD32 has the best real time protection you can get according to the ICSA ratings (the only personal use softare certified for anti-spyware) but the on demand scanner is not ICSA certified. There is very little software for personal use that is ICSA certified, so they are joining a large club. Is there an antivirus software that I can install and use strictly for schedule and on demand scanning that won't conflict with NOD32 and that is ICSA certified on Windows XP Professional? Norton Antivirus is certified. McAfee VirusScan Plus is not certified on XP (and it comes with an uncertified firewall to boot).