I had to replace the cmos battery on the motherboard. I went through the bios and copied everything down, then checked it after swapping out the battery. Nothing changed.

When I try to log in in to Yahoo mail or Gmail I get a page with the following: Secure Connection Failed. Login.yahoo uses an invalid security certificate. The certificate will not be valid until 1/04/2006. (Error code: sec_error_expired_certificate)

This happens weather I use Firefox or Internet Explorer.

Figured it out. When I popped the battery it reset the Date/Time back five years... Resetting it in Control Panel took care of the problem.