Since August, users of HP laptops have encountered system irregularities following the installation of the KB5121003 update for Windows 11. These issues encompass game crashes, unexpected blue screen restarts, and instances where devices become unresponsive on the startup screen. Microsoft has acknowledged the presence of a bug within the update, which predominantly impacts Windows 11 versions 25H2 and 24H2. Notably affected games include Arc Raiders, Marvel Rivals, and The Finals, among several others. The underlying cause stems from modifications made to the kernel handle validation mechanism, resulting in compatibility clashes with third-party drivers (e.g., inpoutx64.sys).

Moreover, certain ARM-based devices experience difficulties in running Microsoft Teams and the latest iteration of Outlook seamlessly after applying this update. As of now, Microsoft has not issued an official resolution and advises affected users to mitigate potential risks by either uninstalling the update or temporarily halting further updates.