To those asking whether a HOSTS file whilst using IE-SPYAD is necessary, this is taken from the Read Me file included with the program itself:- "If I use a HOSTS file, why do I need IE-SPYAD? If you use one of the many custom HOSTS files available on the Net for ad blocking, your HOSTS file will block most ad servers before your browser ever manages to contact them, but there will be occasions when the Restricted sites zone comes in handy. Online marketers are always adding new servers to their stable of ad servers. The HOSTS file (which can be told only about individual servers -- e.g., www.doubleclick.com or ads.doubleclick.com) might not include some of these newer servers, in which case the Restricted sites zone (which can restrict whole domains -- e.g., every server at doubleclick.com) will pick them up. For example, the HOSTS file might know about the ad server adsel16.imgis.com, but if that online marketer starts using adsel66.imgis.com, HOSTS might not recognize it, letting it pass through to your browser. The Restricted sites zone, however, has been told to restrict everything from *.imgis.com (where * is a "wild card" character), and will prevent that ad server from putting a "cookie" on your hard drive once your browser does contact adsel66.imgis.com. In other words, the Restricted sites zone is a kind of insurance policy. Ad servers that pass through the HOSTS file just fine will be restricted by the Restricted sites zone. The one real advantage to using the HOSTS file is that it works at the networking level, blocking ALL outbound network traffic to specified servers, whereas IE's Restricted sites zone (obviously) works only for Internet Explorer. This aspect of the HOSTS file makes it especially useful for controlling Internet access for non-web browser applications like "adware" or "spyware." If you're wondering, I use BOTH, and I've never experienced any appreciable performance hit." I hope this clears up any doubts.