This happened to me when i was trying to login into one of googles service orkut ... lol see http://largepic.net/images/vhklz1fidb41ovzw6r4e.jpg Has it happened with u guys too ??
Experience The security certificate is valid for secured sites for the current year only. So with old date if you try to access any secure site, you will face same issue.
Just like what had nitin22 have said this might be the reason of that. I will bear this unto my mind cos I might encounter such problem in the Future.. Thanks for posting this problem.. Now, I will be aware on this.
That got me to thinking maybe FF should change the alert notification suggesting to check the system date. Great tip by Nitin22!
Ghosh.. I had the same thing a few days back when I re-formatted by Harddisk and reinstalled the windows. Somehow the BIOS was messed up and the date and time was reset. Having trouble with Google, Paypal and some other SSL sites. When I adjusted the clock and calender, the problem was gone.
Yeah the time on your computer makes that error or rather notification shows. It probably pertaining to expiration of site's certificate as per trust level of Fire Fox.