Microsoft Confirms Windows 11 May Update KB5089549 Fails With Error 0x800f0922 on Devices With Limited EFI Partition Space

Microsoft has confirmed that the Windows 11 May 2026 Security Update KB5089549, released on May 12, is failing to install on some devices running versions 24H2 and 25H2. The installation often fails during the reboot process, usually around 35 percent, and displays error code 0x800f0922. In affected systems, the update rolls back and shows a message indicating that changes are being undone.