Microsoft has warned customers about potential system failures due to a blue screen error (secure kernel fatal error) following the installation of Windows updates since March, specifically the KB5055523 April cumulative update and the KB5053656 March preview update, affecting Windows 11, version 24H2. Users may experience crashes and a blue screen exception with the code 0x18B. Microsoft is working on a solution and has implemented a Known Issue Rollback (KIR) to reverse the problematic updates, which will automatically reach affected devices within 24 hours. Affected users are advised to restart their devices. For enterprise-managed devices, administrators must install the KIR Group Policy specific to their Windows version to resolve the issue, requiring a device restart. Further assistance is available on the Microsoft support website. Additionally, Microsoft has released emergency updates for local audit logon policies in Active Directory Group Policy and alerted administrators about potential inaccessibility of Windows Server 2025 domain controllers post-restart.