Microsoft has acknowledged a shutdown issue affecting Windows 11 Enterprise and IoT editions after the January 13, 2026 security update (KB5073455) for version 23H2, which prevents affected systems from shutting down properly, causing them to either hibernate or restart instead. The problem is linked to the System Guard Secure Launch feature and does not affect Windows 11 Home and Pro editions. A temporary workaround involves using the command "shutdown /s /t 0" in an elevated Command Prompt to force a shutdown, but there is no workaround for hibernation functionality. Microsoft is working on a resolution and suggests that enterprise IT administrators consider pausing the deployment of the update on unaffected devices.