Windows 11 Update KB5089573 Addresses Shared Audio and Boot Partition Issues
Severity: Low (Score: 27.9)
Sources: windowsforum.com, Neowin, Notebookcheck, support.microsoft.com
Published: · Updated:
Keywords: windows, update, kb5089573, shared, audio, microsoft, non-security
Summary
On May 26, 2026, Microsoft released update KB5089573 for Windows 11 versions 24H2 and 25H2, enhancing performance and adding features like shared audio support for multiple Bluetooth devices. This update also resolves a known issue from the previous May security update, which affected devices with limited space on the EFI System Partition, potentially preventing installation. Users with less than 10 MB free on the partition are particularly at risk. The update introduces multi-app camera support, improved Task Manager visibility for Neural Processing Units, and enhancements to the Magnifier tool. A registry workaround is available for affected devices, while consumer devices receive automatic mitigation. The update is accessible via Windows Update and the Microsoft Update Catalog. Key Points: • KB5089573 adds shared audio support for multiple Bluetooth devices on Windows 11. • Devices with limited EFI System Partition space may face installation issues. • A registry workaround is available for affected systems to resolve installation errors.
Detailed Analysis
**Impact** Windows 11 users running versions 24H2 and 25H2 are affected by this update, particularly those with hardware featuring limited EFI System Partition (ESP) space (10 MB or less), primarily older OEM devices from 2012 to 2020. The update addresses user experience improvements such as shared audio streaming to multiple Bluetooth LE devices and multi-app camera access, which may enhance operational efficiency. Devices with cramped boot partitions risk installation failures of the prior May security update, potentially leading to system instability or incomplete patching. No direct data breach or loss is reported. **Technical Details** This event involves the deployment of a non-security preview update (KB5089573) that addresses a known installation failure issue caused by insufficient free space on the EFI System Partition, resulting in error code 0x800f0922 during the May 2026 security update (KB5089549). No attack vectors, malware, or CVEs are mentioned. The update introduces new features including shared audio streaming, multi-app camera support, NPU utilization tracking in Task Manager, and fixes related to Windows Hello and magnifier functionality. The known issue relates to Windows Update servicing components and EFI partition management. **Recommended Response** Apply KB5089573 to affected Windows 11 24H2 and 25H2 systems to mitigate installation failures and gain new feature improvements. For devices with limited ESP space, verify free space before deploying May's security update and consider applying the registry workaround (setting EspPaddingPercent to zero) only on confirmed affected machines. Enterprise administrators should deploy the Known Issue Rollback Group Policy and restart affected devices. Monitor Windows Update logs for error code 0x800f0922 and verify successful installation of both KB5089549 and KB5089573.
Source articles (5)
- Windows 11 gets big performance upgrade, shared audio support, and more in new update — Neowin · 2026-05-26
Microsoft is rolling out a new non-security update (also known as C-update) for Windows 11 versions 24H2 and 25H2. KB5089573 with build numbers 26200.8524 and 26100.8524 is now available for download… - Windows 11 update KB5089573: Shared audio & partition fix — Notebookcheck · 2026-05-27
Microsoft pushed the May 2026 non-security preview update on May 26, 2026. KB5089573 moves Windows 11 24H2 and 25H2 to OS builds 26100.8524 and 26200.8524, carrying a set of user-facing additions ahea… - May 26 2026 Kb5089573 Os Builds 26200 8524 And 26100 8524 Preview F378c8ae 0170 47c9 A1e9 Dfef978c8e17 — support.microsoft.com · 2026-05-27
- May 12 2026 Kb5089549 Os Builds 26200 8457 And 26100 8457 28ec2a99 4bbe 481d A340 5c6cf18d9acb — support.microsoft.com · 2026-05-27
- Kb5089573 Windows 11 Preview Efi Partition Space Causes Kb5089549 Error 0x800f0922.419836 — windowsforum.com · 2026-05-27
Timeline
- 2026-05-26 — Release of Windows 11 update KB5089573: Microsoft rolled out KB5089573, enhancing performance and adding features like shared audio support.
- 2026-05-26 — Known issue identified with May security update: Devices with less than 10 MB free on the EFI System Partition may fail to install the previous security update, KB5089549.
- Recent — Registry workaround published: Microsoft provided a registry command to adjust EFI System Partition settings for affected devices, allowing installation to proceed.