Microsoft offers a temporary solution for smart card issues following the October Windows Update, but no long-term fix yet.
In the October 2025 Windows Update, authentication for smart card users was deliberately broken. Microsoft offers a temporary solution in the form of a registry hack.
Incorrect Encryption
After the CVE-2024-30098 Windows 11 update, Redmond noticed issues with smart card certification and other certificates. This occurred because the update required smart cards to use Key Storage Provider (KSP) cryptography instead of Cryptographic Service Provider (CSP). Problems emerged with document signing, smart cards not being recognized in 32-bit applications, and certificate-based application failures.
Temporary solution
Microsoft offers a temporary solution. It allows users to run KSP using a Key Storage API. This means that each affected device needs a registry hack, specifically setting the registry key value to zero. The issue affects all supported and unsupported versions of Windows Server, including Windows 10 22H2.
No long-term solution has been provided yet, and according to The Register, the temporary fix is far from ideal. Using an incorrect key could lead to additional problems.