I'd been having problems using a Personal Identity Verification (PIV) card with my MacBook Pro laptop running OS X El Capitan (10.10.5). I need the system to be able to access certificates on the PIV card in order to be able to decrypt email from some individuals. I have an SCR331 card reader, which attaches to the system via a Universal Serial Bus (USB) port.
If I attached the PIV card reader and clicked on the Apple icon at the top, left-hand corner of the screen and selected About This Mac then clicked on System Report, if I clicked on USB under Hardware, I would see the system recognized the card reader was attached. E.g., I saw "SCRx31 USB Smart Card Reader" for an SCR331 (that is a number on the underside of the device which appears to be its model number with a part number of 904875 listed there, also) PIV card reader I attached to the system via a USB port.
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