Update: Thanks everyone for all the detailed information so far!
We do have a couple of follow-up questions for those of you who have already tried the steps in my previous post.
In the address bar where you see the red Lock Icon, when you click on it you should see a link to see "Certificate Information", please click on that.
When a Certificate window appears, click on the Certification Path tab > expand the tree to find the site certificate, so that we can see the Certificate Status. Please post a screenshot of this too. This detail is important to help us distinguish the different causes of the issue and work on a resolution.
As mentioned in our public issue tracker, please also try disabling third-party shell extensions that may be running on your computer. You can do so by following the steps on this other issue tracker.
Once the third-party shell extensions are disabled, please try the steps outlined here again, and let us know what you find.