I had this problem with photobucket on my downstairs computer. It has something to do with the security. I just used IE for the games and it worked. Try that. If it doesn't work, I don't know what to tell you. Try adjusting the security. :\\
X out of your browser, press ctrl + alt + delete, go to the processes and end the log that corresponds to your browser. It should say Iexplorer for internet explorer, and I believe Firefox says Mozilla. Anyway, it shouldn't be too hard to find. So end that process, open your browser, and try again. It should work then if it's a temporary browser problem.