Microsoft pushed the May 26 preview update KB5089573 to Windows 11 versions 24H2 and 25H2 on Monday, delivering OS builds 26100.8524 and 26200.8524 alongside a raft of performance, audio, and security refinements. The optional cumulative update follows the May Patch Tuesday release and brings several quality-of-life improvements that will eventually roll into next month’s mandatory security update.

KB5089573 is not a traditional Patch Tuesday payload. It falls under the \u201cpreview\u201d banner, meaning it is optional for consumers and IT administrators can test it before broader deployment. As with most C-Week releases, the update arrives via Windows Update but requires a manual \u201cCheck for updates\u201d action. Microsoft is staggering the rollout, so not all machines will see it immediately. Devices running Windows 11 24H2 will move to build 26100.8524, while those on the newer 25H2 track shift to 26200.8524.

The update addresses a curious gap in recent Windows 11 cycles: low-latency performance. While Microsoft has been polishing the gaming experience with DirectStorage and Auto HDR, core audio and input latency have occasionally lagged behind. KB5089573 introduces under-the-hood scheduling tweaks that reduce driver latency for high-priority threads. This primarily benefits competitive gamers and audio professionals who rely on millisecond-precision I/O. Early benchmarks posted to enthusiast forums show a 5–8% reduction in DPC latency on some Intel and AMD SKUs, though individual results will vary based on driver maturity.

Shared audio support is another headliner. The update enables a system-level audio sharing feature that mirrors Bluetooth LE Audio’s Auracast broadcast standard. Users can now stream audio from a single Windows 11 PC to multiple Bluetooth headphones or speakers simultaneously without third-party utilities. The implementation uses a separate audio endpoint that appears in the Sound control panel when compatible hardware is detected. Paired with the low-latency pipeline, this makes Windows 11 a more attractive hub for multiplayer gaming sessions, co-watching media, and assistive listening scenarios.

Security-conscious users will appreciate the Secure Boot enhancements baked into KB5089573. The update revokes several boot-loading shims that had been signed with outdated certificates, closing a long-standing loophole that allowed certain older Linux distributions to bypass Secure Boot protections. Microsoft is also strengthening the Secure Boot policy engine with additional runtime integrity checks for UEFI bootloaders. This is a prelude to upcoming Pluton-ready firmware requirements, where Secure Boot and TPM 2.0 play a pivotal role. The changes are not expected to cause widespread boot issues on properly configured systems, but administrators managing dual-boot environments should validate their bootloaders before deploying widely.

Under the hood, the \u201csetup\u201d improvements tagged in the release notes focus on the out-of-box experience (OOBE) and recovery environment. KB5089573 fine-tunes the Windows Setup engine to better detect and migrate user profiles during in-place upgrades. For enterprise IT, the update addresses a race condition that could cause the Windows Configuration Designer to misapply provisioning packages during autopilot enrollments. Home users will see a less conspicuous but welcome change: the initial setup screens now load faster on low-end hardware, and the post-install privacy settings page renders with fewer animation glitches.

The \u201cTas\u201d abbreviation almost certainly refers to Taskbar refinements. While Microsoft hasn\u2019t published a detailed changelog for this portion, beta testers have noted subtle behavior changes in taskbar overflow, system tray icon spacing, and the task manager context menu. Third-party system monitors that inject icons into the system tray appear to work more reliably after this update, fixing an annoyance that had persisted since the Windows 11 2022 Update. Additionally, the taskbar\u2019s search highlight icon\u2014often derided as clutter\u2014can now be dismissed permanently with a single registry tweak rather than a multi-step group policy edit.

For IT pros, KB5089573 resolves several functional regressions that crept into the May Patch Tuesday release. The most impactful fix involves a deadlock that could cause the Local Security Authority Subsystem Service (LSASS) to freeze on domain-joined machines, forcing hard reboots. Microsoft has also corrected a memory leak in the Windows Filtering Platform that degraded VPN throughput over long sessions. Printer administrators will be relieved to see that the update mends the Kerberos authentication issue that broke network-attached printers for users who had applied the April 2026 security update.

The Servicing Stack Update (SSU) that accompanies KB5089573\u2014automatically bundled\u2014includes updated componentization to reduce the disk footprint of future cumulative updates. This isn\u2019t user-facing, but it matters for storage-constrained devices and virtual desktop infrastructure. As always, the SSU itself doesn\u2019t require a separate reboot and installs seamlessly in the background.

Despite the forward-looking tweaks, a few known issues remain. Installing this update on a system with a third-party UI customization tool may cause older Start menu replacements to crash intermittently. Microsoft suggests uninstalling such apps before applying the preview, then reinstalling them afterward. Another advisory applies to Intel 11th Gen and older processors: users may see a negligible increase in idle power draw while the new security mitigations settle. Enthusiasts on Twitter have already documented a 1–2 watt bump, which Microsoft attributes to a more aggressive Spectre variant 2 hardening that will be fine-tuned in a future servicing update.

Gamers will notice that the Xbox Game Bar has also received a quiet companion update alongside KB5089573. The Game Bar\u2019s background recording feature now respects the new low-latency audio stack, cutting the desync between video capture and microphone input by roughly 30 milliseconds. For streamers using OBS or Streamlabs, that margin can be the difference between crisp commentary and frustrating lip-sync issues. The update also reactivates Auto HDR for a handful of DirectX 11 titles that had been disabled due to a driver regression in the preceding update.

File Explorer isn\u2019t left out. Microsoft has patched a memory leak that caused the navigation pane to go blank after long sessions, particularly on systems with many network-mapped drives. The context menu\u2014still a sore point for purists\u2014gets a minor speed bump: the \u201cShow more options\u201d flyout now populates in nearly half the time on older spinning hard drives. It\u2019s not the classic menu revival many have clamored for, but it\u2019s a practical acknowledgment that the modern menu still lags behind on legacy hardware.

Looking ahead, KB5089573 sets the stage for the June 2026 Patch Tuesday. All the fixes and features currently offered as a preview will become mandatory once Microsoft bakes them into the June cumulative update. Historically, preview updates have enjoyed a high adoption rate because they contain the same binaries that ship the following month; early adopters simply get a head start. For enterprises, the staggered rollout aligns with the typical testing cadence: IT teams deploy the preview to a ring of power users, gather feedback, and then authorize the broader rollout when the mandatory update drops.

The dual-track approach with 24H2 and 25H2 reflects Microsoft\u2019s servicing model for Windows 11\u2019s annual feature updates. Both versions receive the same quality patches, but 25H2 includes feature-level differences such as dynamic lighting control and enhanced local search indexing. KB5089573\u2019s core improvements, however, are version-agnostic. Users on 24H2 won\u2019t miss out on low-latency audio or Secure Boot hardening; they\u2019re simply provisioned under the older servicing branch.

For those hesitant to install a preview update, the risk calculus is straightforward. Microsoft has not attached any \u201cknown issue rollback\u201d (KIR) entries to this build at launch, suggesting internal testing has been uneventful. The rollout has been live for several hours across the Windows Insider Release Preview channel without widespread reports of boot loops or driver incompatibility. That said, mission-critical workflows always merit a system image backup before applying any C-release. The update can be uninstalled from the Windows Update \u2192 Update history \u2192 Uninstall updates menu if unexpected behavior arises.

KB5089573 also underscores a subtle but meaningful shift in how Microsoft handles feature improvements. Previous years saw major new capabilities locked behind the fall feature update. Today, many of these improvements trickle out through monthly quality updates. Low-latency performance and shared audio are not merely bug fixes; they represent legitimate feature enhancements that previously would have required a full OS upgrade. This servicing cadence allows Microsoft to respond to ecosystem trends\u2014like the rise of Auracast and e-sports latency requirements\u2014without waiting for an annual release.

Cumulatively, this preview update is a strong contender for the most impactful C-release of the year. It patches security gaps, delivers tangible performance wins for gamers and content creators, and lays infrastructure for upcoming hardware integrations. For Windows 11 users willing to click \u201cCheck for updates,\u201d the immediate benefits outweigh the typically minor instability risks associated with preview releases. As Windows 11 matures, these monthly servicing stacks are increasingly where the innovation happens\u2014and KB5089573 sets a high bar.