Problem with Java on website

I have an extremely frustrating issue with Java.  The computer has Windows 7 64-bit.  The website the user is trying to get to is catalog.comstarsupply.com.  When you add something to the cart, a picture of gears and a loading box comes up and doesn't go away.  If you click to go right to the cart, it just sits there.  The user has no issues with any other sites.  I even went to a site that tests java, and had no issues.  I've tried Firefox and chrome...I've tried uninstalling all browsers, including IE, uninstalling Java, rebooting, and reinstalling just IE and java....still the same issue.  I tested the site from a few other computers on the same network and can access it just fine.  I also tried IE 7, 8, and 9.