kernel driver blocking

Kernel driver blocking refers to Microsoft's practice of intentionally preventing vulnerable kernel-mode drivers from loading as part of Windows security updates. This tag covers discussions about updates that block specific drivers, such as psmounterex.sys, which can cause third-party backup applications to fail when mounting or managing disk images. The tradeoff involves improved kernel protection versus potential breakage of tools that rely on older privileged driver code. Topics include Windows 11 and supported Windows versions, cumulative updates, driver vulnerabilities, and the impact on enterprise IT environments where backup software is critical for recovery operations.