system
4
Start avast!, click on the menue item in the left upper corner. Then you get a pull down menue with an item that’s called “Timer for Boot Time Scan” (or so. Have to translate it from german to english…)
Boot Time Scan is a scan of the entire drive or a specific folder before Windows starts (works only in WIN2000/XP). So there are no files occupied and avast! can scan them.