thanks both of you…
the link you provided is sufficient for me:smiley: :smiley: :smiley:

copied from this link–>http://blog.avast.com/2010/09/06/spring-cleaning-in-our-virus-database/

Now it is time to clean up and reduce the number of unnecessary detections. The main reason for this is to decrease the size of our virus database updates sent to users around the globe. This will reduce the amount of transferred data, subsequently reducing the amount of needed energy and helping, of course, our forests