Dude.. dont post consecutivelly... use the EDIT button u see...
NAV 2005 hogs more memory than the 2003... if u really want norton then go for the 2006 version.. its a lot faster than 2005 and is almost as good in speeds as 2003
also.. to disable the tray agent do this :
Norton Antivirus > Options > under the Autoupdate tab (ususally the first page) uncheck the box marked Show Auto-Protect icon in tray. and save thee settings
