make sure you're using the EV client from EV 11.0.1 CHF3 or CHF4
I know this thread is a few months old, but I just stumbled across this issue and we figured out a cause.
In this case, the Mac was using Outlook 2016, and both the Outlook and Mac versions were verified as being supported.
The reason that the EV client extensions couldn't recognize Outlook and check the version was that it was not installed at the top-level program folder. Apparently the client won't drill down from the top level at all when checking for Outlook, so if it's been installed in its own folder, the extensions won't find it unless you install the extensions in the same folder as Outlook.
Hope that helps!
