January 2026 was a problematic month for Microsoft and Windows updates, with the company confirming new bugs on a weekly basis. Some of these bugs were very serious, such as device startup failure with the message “UNMOUNTABLE_BOOT_ERROR”, while others were rather funny, such as the inability to shut down of a computer or attempts to hibernate. Microsoft tried to fix this bug with an out-of-band update, but as it turned out later, the problem affects even more devices than Microsoft thought.
The company has updated the official Windows Health Dashboard documentation to clarify that the shutdown and hibernation issues also affect computers with Secure Launch and Virtual Secure Mode enabled. The latter is a virtualization-based technology that keeps sensitive information in a protected area for added security. If your device is using Virtual Secure Mode, it may not shut down or hibernate properly after installing recent Windows updates.
