You must allow cookies for these type of sites and have JavaScript enabled in your browser. I suggest clearing the browser's cache and make sure you are accepting all cookies from the site aling with having JS enabled. Some sites use Java so be sure it is updated and also enabled.
Clear Your Browser's Cache (All Browsers): http://www.wikihow.com/Clear-Your-Browser%27s-Cache
How and Why to Clear Your Cache: http://www.microsoft.com/windows/ie/ie6/using/howto/customizing/clearcache.mspx
How to Enable Cookies in Your Web Browser:
http://support.hubris.net/knowledge_base/039.html
http://www.2privacy.com/www/enable-cookies-disable/enable-cookies.html
How do I enable Java in my web browser?:
http://www.java.com/en/download/help/enable_browser.xml
How do I enable JavaScript in my browser? (Covers all browsers):
https://www.google.com/adsense/support/bin/answer.py?hl=en&answer=12654
Includes AOL versions: http://www.buymebuyme.com/retail/help/javascript.html
Ron