Secure connection failure in browser for https sites
Recently I kept getting the error message "Secure Connection Failure" when using Firefox to go to https sites. I had a similar problem when I tried using Safari to connect to https sites.
I fixed the problem by opening System Preferences > Parental Controls > selecting the appropriate User (as long as you have administration rights) > selected Allow unrestricted access to websites (by default Try to limit access to adult websites automatically is selected).
Once I checked unrestricted access I was able to go to the https sites I wanted, which were my bank's site and the Firefox homepage for FAQs. Then I went back and checked "Try to limit ...". That brought back the error message again so I checked "Allow unrestricted access ...".
The issue may have arisen because I downloaded a system security update a few days ago. Perhaps it reset the Parental Controls default.
It would be good to block adult sites but the alternative seems to be to customize in Parental Controls the sites that are OK. This would be a tedious job because so many sites are https eg this site.
I no longer have a problem but thought this might help others.
iMac (21.5-inch Mid 2010), Mac OS X (10.6.8), Also older Macs