Why are some anti-virus systems free while others have to be paid for?

AVG7.5, avast, Windows Defender, Spybot - Search %26 Destroy - all free. Norton, McAfee and others cost an arm and a leg.......why?

Why are some anti-virus systems free while others have to be paid for?virus

very good question...basically its down to the companys making money from their other products to cover the upkeep of the free products

companys such as a.v.g and avast who give free anti-virus programs by download also have paid for versions which have a few added extras compared to the free versions

in the case of spy-bot they rely on donations which you can pay through the donation link in the program,and its in our interest to donate a few quid to keep this excellent program running

windows defender is free basically because its going to be part of "vista" and is used in windows xp as a beta,but microsoft can afford to give this program as free

norton hasnt gone for the free route as i think they are scared of it affecting their payed versions,so if people know there is a free norton anti-virus they will use that instead as its called"norton"

in my opinion free anti-virus software is just as good as paid versions,but its down to the user,if you feel safe using a free version then thats ok,but its all down to personal preference

good luck

Why are some anti-virus systems free while others have to be paid for?anti virus