Microsoft will enforce a new mandate requiring all hardware drivers to comply with the Windows Hardware Compatibility Program (WHCP) standards starting April 1, 2026. This change will eliminate the "cross-signing" system that allowed older drivers with expired certificates to remain trusted. The enforcement of WHCP certification will apply to various versions of Windows 11 and Windows Server 2025. Users may face blocks when installing older drivers on new systems, but existing installations will not be immediately disrupted. Microsoft plans to introduce an "allow list" for vetted legacy drivers to ensure essential equipment remains operational during the transition. The initial rollout will occur in "evaluation mode," allowing Microsoft to monitor driver behavior without blocking software. For corporate environments, Microsoft offers "Application Control for Business" to allow specific software while maintaining security measures.