Butch,

Submitting a ticket with logging info would be helpful to get started.

- Shawn
_____________________________________________________________________
Shawn Geddis            geddis@{Mac | Me | iCloud}.com
Security and Certifications Engineer, Apple                geddis@apple.com

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_____________________________________________________________________

On Dec 2, 2015, at 12:35 PM, Butch McCarty <butch.mccarty@gmail.com> wrote:
Hello sir or ma'am,

I recently upgraded from Yosemite v10.10 to El Capitan v10.11. As soon as the upgrade was complete, I downloaded the new v2.1.2 installer, ran it successfully, but after I attempt to get onto my.af.mil, I get the "CAC error" screen. This doesn't happen on my other computers and I have swapped out the card readers, which all work on other computers. Is there any fix to El Capitan? 

--
V/r,
Butch McCarty