Start at http://www.lenovo.com/products/us/en/
With Internet Explorer, clicking on the links 'Desktops" or 'Notebooks' is error free. With Firefox, doing so produces a Certificate Error, 'Could not verify this certificate because the issuer is unknown'. The OU is VeriSign, Inc., the Organization is VeriSign Trust Network.
Duplicating the issue has proved impossible from the same computer. Reinstalling FF does not help. My knowledge of certificates is limited; my best guess at troubleshooting was to copy the page's sourcecode to a local HTML file, and try from a new install of Firefox on a new computer. This did not generate the warning.
Maybe I need more help in understanding how to troubleshoot this, perhaps a way to duplicate the problem from the same computer.
The problem is the warning should not appear until clicking 'Checkout', many steps later in the process. Please help me learn the cause.