If you want, I can produce a concise checklist you can print and follow during troubleshooting.

Major Windows 10 updates (such as v1903 and later) have been known to remove custom registry keys required for smart card readers to communicate with the system. Driver Signature Enforcement:

Some modern UEFI motherboards handle USB differently.

Manual Registry (if PowerCFG fails):

driver war

The "Setool2 Smart Card Not Found" error on Windows 10 is rarely a hardware failure—it's almost always a between Microsoft's native smart card stack and the legacy USB access required by Setool2.

Manual Registry Restore

: Manually rebuilding the Calais\Readers keys or applying specific Microsoft patches (like KB4515384 ) to prevent Windows from ignoring the reader.