The UMDF 2 host process ( UMDFHost.exe ) loads the driver DLL. This driver exposes the smartcard reader as a standard SCARD_READER device to the Windows Smartcard Resource Manager (SCardSvr).
Add a DWORD registry key RetryDeviceInitialize with value 1 at HKLM\SOFTWARE\Microsoft\Cryptography\Calais\Readers .
The most interesting part of the name is the tag. This isn't just a version number; it tells us exactly where the driver lives in your computer's brain.