My computer won't allow any games to connect?

It's pretty simple and straightforward. My computer won't allow ANY games to connect to the internet. At all. The only ones that work are Combat Arms and Runescape, because they connect through the browser. (Out of browser RS client doesn't work). I've tried EVERYTHING. Firewalls. Anti-virus. Ports. Temp cache. Hidden files. All of it. HELP ME PLEASE. >.<