Web pages close automatically

I've had this problem for a while and cant seem to get rid of it. Basically what happens is when I go to some web sites, the web page will just automatically close before loading anything. It only happens on some sites, but with those sites it happens every single time I try to go to them. I've tried using Internet Explorer, Mozilla, and AOL's browsing page, but it still happens with all of them. I have downloaded a bunch of virus and spyware removal programs but nothing seems to help so I don't even know if it is something like a virus but I'm not sure what else it could be. If anyone could help it would be greatly appreciated. Thanks!