hi europaguy, which security program are you using?

https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

https://support.mozilla.org/en-US/kb/secure-connection-failed-error-message

https://support.mozilla.org/en-US/kb/connection-untrusted-error-message

http://kb.mozillazine.org/Error_loading_websites

This Connection is Untrusted is sometimes caused because the computer system clock is wrong. Check the time / date / time zone settings. https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

philipp said

hi europaguy, which security program are you using?

Bitdefender Total Security 2015

thanks, can you try to disable ssl scanning in bitdefender's options and see if this is making a difference? http://www.bitdefender.com/support/what-to-do-when-security-certificates-cannot-be-verified-installed-1090.html

philipp said

thanks, can you try to disable ssl scanning in bitdefender's options and see if this is making a difference? http://www.bitdefender.com/support/what-to-do-when-security-certificates-cannot-be-verified-installed-1090.html

The problem was SSL Scanning in Bitdefender and they say there will be an update shortly to rectify the issue. I just had to open the Bitdefender interface, go to Protection, then web Protection and switch off SSL Scanning. Thanks for your help