A few days ago, Microsoft released update KB5077181 for Windows 11 (both 24H2 and 25H2). Now, some reports (via Neowin) are emerging that the new version is causing boot problems for users. The critical startup problems appear to occur immediately after installation, causing those affected to end up in an endless loop of restarts.
In some cases, a SENS error message (System Event Notification Service) error appears. This usually means that the system can’t interact with the service due to missing data or network problems. Other users are seeing error codes 0x800f0983 and 0x800f0991.
Some users, on the other hand, report that their systems display a DHCP error due to a missing connection or an invalid IP address, even though they’re connected to the internet. There are numerous problems with the patch that can’t yet be clearly explained.
What you can do about it
There’s currently no fix from Microsoft and the boot problems aren’t listed in the list of known issues with the update. Since users are unable to log in even after several loops, some have tried to reset their systems via recovery mode—to varying degrees of success.
If you can, uninstall the update via Control Panel > Programs > View Installed Updates and selecting KB5077181. After that, you must still suspend automatic updates by Microsoft by navigating to Settings > Windows Update > Pause Updates. Otherwise, the update may be reinstalled and cause problems again.
Further reading: How to roll back a problematic Windows update