The beta version I have is a developers' version. It updates every week and is newer than the Final Release. The latest update was 1/31/2020.
See if you get prompted to log in to this site or get the "Hmm... can't reach this page"
I reinstalled the release version, and I get the same results.
It's interesting because I can access that page and others that give the same error in Internet Explorer.
I was also able to get to the site via "auth.ultimatix.net" and "https://www.ultimatix.net". One other issue is when I do sign in, it makes me authenticate twice. It is not supposed to do that. Other browsers do not cause that issue. When looking with Developer Tools, it seems that something is going on with the cookies. I'm awarding @Bill Prew the answer, but additional information might be of value if there is a followup on the double authentication part.
Why you are not installing the final version of Microsoft Edge ?
Kidney find the below link to download: