In some pages, e.g. Twitter, and pages that load FB comments sections, I'm having problems with the certificates and the pages won't load. I don't get an option to add an exception either, therefore I cannot access pages.
I have pasted the error details below. Here is some important info for you:
Version: 9.0.1 <-- Upgrading is NOT an option, this is a corporate machine
Connect via proxy: yes
I doubt very much that this is an issue with the connection, as IE and Chrome are NOT having this issue on the same connection.
Error I get:
This Connection is Untrusted
You have asked Firefox to connect securely to twitter.com, but we can't confirm that your connection is secure.
Normally, when you try to connect securely, sites will present trusted identification to prove that you are going to the right place. However, this site's identity can't be verified.
What Should I Do?
If you usually connect to this site without problems, this error could mean that someone is
trying to impersonate the site, and you shouldn't continue.
twitter.com uses an invalid security certificate.
The certificate is not trusted because the issuer certificate is not trusted.
(Error code: sec_error_untrusted_issuer)
Can anyone shed some light? The usual troubleshooting I've come across hasn't helped me much.
Re: Having some problems with security certificates
Off the cuff it smells of a man-in-the-middle situation to me. As far as I know, Twitter does have a valid certificate, signed by Verisign. That IE and Chrome have no problem with it, could just mean they do not check resp. do let you know.
I'll have to pass here, because I would not know, how to turn this checking off in FX 9.0 - in any case I would think twice before doing it. The place to look would be Options > advanced > Encryption.
Hope somebody else joins us
PS: keeping you nailed down to Fx 9.0 version is unsafe - not just for you, but for your company as well.