Have you tried clearing your browser cache?
Also maybe try to clear your DNS cache as well.
Type ipconfig /flushdns into a command prompt. I assume you're using Windows.
Do you use any "ad blocking" software?
One very very long shot could be a MITM attack. It's possible your traffic is being sent through an appliance that intercepts the web traffic and performs content inspection. This would cause the certificate to change and be replaced by the appliance's own certificate.
FYI I live in EU and the lovely EU still tries to censor rt.con
From a purely technical point of view, this MITM attack is quite clever, by messing up with the expiry date you do not even have to "crack" the certificate, just mess up with the date and the browser will censor the website.
BTW now it is working .... so .... whatever it was it has been "adjusted"
(post is archived)