This problem appeared on my brother's computer, I'm not sure when. On his Child account he can not access certain secure connections, however, on the Admin account I have set up, I can. There is obviously either a problem with the account or a problem with the Family Safety settings, though previously I had the Family Safety settings exactly the same (I recently did a factory reset on the computer, as it was full of crapware which simply needed to go) and I think that even after I reset it and set up the family safety he was able to access YouTube and such, the web filter blocked certain ones but it'd come up with it's unique family safety page, meanwhile this simply says that the "secure connection failed". This problem occurs on both Firefox and on IE, so I know it isn't a problem with the browser. I already looked at the HOSTS file in C:\windows\system32\drivers\etc and there have been no alterations made to it. I flushed the DNS cache to no avail and even set up an Advanced Firewall rule for port 443, eventually disabling the firewall completely to see if that was causing it, but no potatoes. Any clues?