Question 1

Install fails/rolls back?

Accepted Answer

Disconnect the reader, uninstall any existing SCR3310/SCM driver in Device Manager with hidden devices shown, reboot, then run the installer as administrator. Confirm the package matches Windows version and 32/64-bit.

Question 2

Reader not detected?

Accepted Answer

Try another USB port, preferably rear USB 2.0, reseat the cable, and check Device Manager for Unknown Device or Smart Card Reader. Remove/rescan the device and ensure the Smart Card service is running.

Question 3

Driver version conflicts?

Accepted Answer

Windows’ CCID driver can load alongside an old SCM package. Remove duplicate SCM/SCR3310 entries, reboot, and install only one signed driver. Avoid stacking multiple SCR3310 packages.

SCR3310 v2.0 USB Smart Card Reader Driver