I am having trouble with using DUO authenticator, its saying that my my Mac OS X is out of date when I just updated to the newest software that's available. Can you guys help?

Check software update. 10.15.7 is the current release of macOS Catalina.

What version are you actually running?

If you're running Big Sur, the application probably doesn't know how to deal with the 11.x.x version number. In that case, contact the developer.

Yes, the application developer. Their app believes you are running 10.15.6, which is clearly incorrect. They need to update their application to correctly interpret the version number now that it's gone from 10 to 11.

It thinks you're running 10.15.6 !???

In bout this Mac click on the Version number & what build number shows up?

20D64F

20D74

20D75

20D80

Showing it in my Mojave install...

Never be afraid to ask questions... unless you grew up in my household!

I have to assume you're correct, whoever administers it must make a change...

https://duo.com/docs/policy#operating-systems

What user agent does yours report?

https://www.whatismybrowser.com/detect/what-is-my-user-agent

Actually, it should be 20D80 for the released version of macOS 11.2.2.

I'm having this same issue with Duo - including that it thinks I'm on 10.15.6, when I'm actually on BigSur 11.2.3. Anyone else figure out a solution?

I just found this article on Duo's site, though not sure what to make of it: https://help.duo.com/s/article/6627?language=en_US

I can usually understand these types of articles, but that Duo article had me scratching my head a bit, although it’s clearly on point. Is the fix that the system admin needs to reconfigure the Duo setup on their end so that the end users don’t get the wrong OS message? I don’t think that there was anything the end user could do? Sorry for a basic question.

Great find my friend! :) 👍