Microsoft's latest Patch Tuesday update for Windows 11 is causing trouble for some users. The KB5089549 update, released on May 13, 2026, is reportedly failing to install on certain computers, while a smaller group of users reports that the patch also slows internet performance after installation.
The reports started appearing shortly after the update rolled out through Windows Update (via Neowin). The majority of complaints are coming from users posting on forums like Reddit (links 2 and 3), where affected systems repeatedly attempt to install, then roll back to the previous version. The issue appears tied specifically to Windows 11 systems running the May 2026 cumulative update.
