Windows Code Signing Overhaul Set for October 2026

Microsoft is warning IT teams and software developers that they must prepare for significant changes to Windows code signing by October 2026. The existing Windows Production PCA 2011 certificate will expire at this time, prompting Microsoft to transition to stronger cryptographic standards.

The company aims to adopt RSA-3072 and SHA-384, which are considered more secure than the current methods used. Post-quantum cryptography is also expected to become part of Windows code signing in 2027, enabling protection against potential future quantum-computing threats.

Microsoft warns that applications tied to the old certificate could experience compatibility issues or stop working properly after the transition. IT teams are advised to take a close look at the software running in their environments and engage with key software vendors to confirm that their products use Microsoft's supported trust-validation mechanisms.