Why can't ukey recognize the social security digital certificate?

In general, the CA certificate is installed on a key such as a USB flash drive. The reason why these keys don't respond when plugged into the computer is that they can only be recognized and used after the driver is installed. The solution is: go to official website, which issued the CA certificate, download the corresponding certificate driver, download and install it directly, and then insert the key with the CA certificate, and you can identify it this time.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.