Hello Josh,
Thank you for posting in Q&A forum.
Based on the description, you cannot use a smart card to access certain websites all of the sudden, you can troubleshoot the problem as below:
1.Please check the certificate in your smart card is not expired.
2.Please check if you can access other apps or sign in the Windows using the same smart card. I mean if the smart card itself is OK.
3.Please check if the smart card reader itself is OK.
4.If you use smart card in the virtual environment (such as Azure Virtual Desktop), please restart the virtual environment and check the result.
5.Based on the description "websites will no longer prompt me to select my certificates", what prompt did you receive? Please check the issue based on the error message or prompt message.
I hope the information above is helpful.
If you have any questions or concerns, please feel free to let us know.
Best Regards,
Daisy Zhou
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