Windows 11 25H2 Known Issues: DRM Playback, WUSA Errors, Arm64 Tooling

Microsoft has confirmed a set of known issues in Windows 11 version 25H2, the 2025 feature update now rolling out to consumer and enterprise devices, and some of those bugs carry practical impact for media playback, update installation workflows, and certain device architectures. Microsoft’s release-health notices list the problems, and community reporting has already surfaced real-world encounters — meaning IT teams and power users should plan mitigations before attempting a broad deployment.

Background / Overview​

Windows 11 version 25H2 (the “Windows 11 2025 Update”) is delivered as a servicing-enabled update, intended to be small and fast for users already on recent builds. Microsoft’s official rollout notes reinforce that feature parity with 24H2 was retained while enabling several Copilot+ features and enterprise connectivity improvements. The update’s deployment model aims for minimal downtime, but Microsoft is also publishing known issues and temporary mitigations as they appear in the field.
What’s important to understand is that the known issues list is actively maintained: some problems affect only legacy or niche workloads (for example, apps relying on older media pipelines), while others can break administrative workflows (such as installing .msu packages from a network share). Microsoft marks severity and provides mitigation or rollback options for organizations that need to retain service-level stability while fixes are developed.

---

What Microsoft has confirmed: the main issues​

1. DRM / Protected-content playback failures in some apps (Enhanced Video Renderer / HDCP)​

Microsoft states that some Blu-ray/DVD and Digital TV applications which rely on the Enhanced Video Renderer (EVR) with HDCP enforcement or certain DRM-based audio handling may fail to play protected content. Symptoms include copyright-protection errors, playback interruptions, freezes, or black screens. Streaming services (modern UWP or web-based apps) are not impacted, but legacy media players and hardware-tethered TV apps may be.
Why this matters: organizations or users who routinely rely on physical media or specialized broadcast capture applications — for example in broadcast production, digital-archival workflows, or classroom setups with legacy apps — can lose significant functionality until a fix is available. This is not a universal media failure; it’s specific to apps that use older DRM enforcement paths.

2. Windows Update Standalone Installer (WUSA) fails when run from a shared folder containing multiple .msu files​

Administrators installing updates manually using WUSA (wusa.exe) from a network share could encounter ERROR_BAD_PATHNAME when attempting to run .msu installers by double-click or WUSA against a share that contains multiple .msu files. The problem is tied to interactions between devices with 25H2 and SMB networking stacks, and it may surface when either the SMB client is on 25H2 or the SMB server includes specific cumulative updates. Microsoft’s guidance indicates a workaround that forces SMB to use TCP rather than legacy NetBT naming fallback.
Why this matters: many corporate patching workflows still use network shares, manual installs, or offline servicing scenarios. If your deployment processes depend on double-clicking .msu files from a file share, expect potential failures until the underlying issue is resolved.

3. Media Creation Tool incompatibility on Arm64 hosts​

Microsoft has indicated that the Media Creation Tool version released with the 25H2 availability may not run as expected on Arm64 devices. The Media Creation Tool is a common way enthusiasts and admins create bootable media or ISO images; this limitation is targeted at Arm64 hosts rather than x86/x64. Microsoft’s documentation and release notes flag this behavior and typically follow up with a corrected tool or guidance.
Why this matters: the Arm-based PC market — while smaller than x86 — is important for organizations using Windows on Arm devices and for DIY installers. The inability to produce updated installation media on Arm64 hosts complicates offline build processes and image servicing scenarios.

4. Related regressions and ongoing investigations (examples from preview updates)​

Separate but related regressions that surfaced around preview cumulative updates (for example in May 2025 previews) included text-rendering issues with Noto CJK fonts, virtualization and external-drive VM problems for some users, and device-specific driver problems. While those issues were tied to earlier preview or patching cycles, they demonstrate how cumulative updates can introduce regressions that later require Known Issue Rollback (KIR) or targeted fixes.
Why this matters: history shows that preview/optional updates can generate problems that later propagate; administrators must pay attention to preview channels and apply standard QA to test builds before broad rollout.

---

Technical details and root-cause signals​

Enhanced Video Renderer and DRM handling​

• The EVR pipeline is older Windows multimedia infrastructure used by many legacy Blu-ray and TV-tuner apps. When EVR is used with HDCP enforcement or with certain DRM audio stacks, the system must ensure cryptographic and pipeline invariants to prevent content copying.
• Microsoft’s troubleshooting notes indicate EVR-based DRM enforcement behaviors changed or regressed in 25H2, which leads applications to fail validation and abort playback. This is distinct from modern streaming DRM (Widevine/PlayReady via modern app frameworks), which the company says is unaffected.

WUSA / .msu install error flow​

• The ERROR_BAD_PATHNAME symptom suggests a path-parsing or SMB client/server behavior change when multiple .msu files exist in the target directory and connections fall back to NetBIOS/NetBT name resolution instead of TCP SMB.
• Microsoft’s practical workaround — making sure SMB traffic uses TCP port 445 — nudges the connection away from NetBT and avoids the failure mode. This points to a protocol-fallback bug rather than a pure file-installer bug.

Media Creation Tool on Arm64​

• The Media Creation Tool is often a small wrapper that orchestrates downloads and image assembly. Failure on Arm64 hosts frequently means the tool’s packaged binaries or one of its dependent components lacks full testing on the Arm64 host ABI.
• Microsoft typically releases a patched tool once the regression is validated; until then, alternatives include using official ISO downloads or x64 host creation methods.

---

Who is affected (scope and severity)​

• Consumers using mainstream streaming apps: unlikely to be affected. Most streaming providers use modern DRM stacks; Microsoft explicitly states streaming services aren’t impacted by the EVR regression. However, users of older DVD/Blu‑ray players, TV tuner or capture applications, and specialized broadcast tools may see failures.
• IT administrators and SCCM/WSUS-managed environments relying on .msu-based or network-share-based manual installs: more likely to be affected by the WUSA error, particularly where legacy SMB configurations or NetBT naming remain in place.
• Enterprises with Arm64 imaging workflows: impacted if they rely on the Media Creation Tool on Arm64 hosts to generate media.
• Edge cases and smaller markets (e.g., some Intel 11th‑gen audio driver interactions from prior updates): historically, a minority of devices but with high visibility when they occur — these are typically isolated to specific driver or vendor stacks and may take longer to resolve.

Severity assessment:

• The DRM/EVR issue is functionally severe for affected media workflows but low impact for most consumers.
• The WUSA/.msu issue is administratively severe for organizations relying on manual share-based installs.
• The Media Creation Tool incompatibility is an annoyance with limited operational impact if alternate imaging paths are available.

---

Practical mitigations and step-by-step actions​

Immediate consumer guidance​

• If you primarily use modern streaming services (Netflix, Prime Video, Disney+, YouTube), proceed normally; those services are not affected.
• If you rely on DVD/Blu‑ray or legacy TV capture apps: delay upgrading production machines to 25H2 until Microsoft issues a fix, or validate functionality on a test device first.
• If the Media Creation Tool on your Arm64 device fails, download the ISO using Microsoft’s official ISO channels on an x64 host or use the Windows 11 ISO from the Microsoft update portal until the tool is fixed.

For IT administrators and enterprise teams​

• Don’t push 25H2 broadly until you’ve:
• Tested the update in your device diversity lab (covering virtualized, physical, Arm64, and legacy hardware).
• Verified that any line-of-business apps that use legacy media pipelines still work.
• Confirmed that your update distribution process (WSUS, SCCM/ConfigMgr, Intune) is not impacted by WUSA network-share installs.
• If you must deploy and encounter the WUSA ERROR_BAD_PATHNAME behavior:
• Ensure SMB connections use TCP instead of falling back to NetBT. Allowing traffic on TCP port 445 between client and file server forces the TCP SMB path, which Microsoft identifies as a working workaround.
• As a more robust approach, use WSUS/SCCM to distribute updates rather than manual network-share .msu files. This avoids WUSA scenarios entirely.
• Use Known Issue Rollback (KIR) policy for managed machines:
• Microsoft provides KIR policy definition MSI files for enterprise Group Policy deployment; applying the KIR will roll back only the change that caused the problem without removing security updates. Enterprises can configure KIR via Group Policy in Active Directory or hybrid Entra deployments. This is the supported enterprise mitigation for nonsecurity update regressions.

Step-by-step: check your Windows version and build (short)​

• Open Settings > System > About, or run Winver from Start.
• Confirm you see Windows 11 and a build number that indicates 25H2 (check Microsoft’s update history for the exact build numbers at the time of rollout).
• If you see issues and you’re on 25H2, reproduce the problem on a test lab and gather logs (Event Viewer, Reliability Monitor, Feedback Hub traces) before applying rollbacks or workarounds.

---

Deployment strategy recommendations​

• Staged rollout: apply the update to a limited, representative pilot group that includes users with:
• Legacy media playback requirements.
• Machines that use manual .msu install workflows.
• Arm64 devices used in imaging or development.
• Test with real-world workflows: especially capture-to-disk, broadcast ingest, and network-based offline patching.
• Retain the capability to perform KIR or to roll back cumulative updates at scale using your management platform.
• If you rely on vendors (e.g., OEM audio drivers, broadcast software vendors), check vendor advisories for compatibility notes tied to 25H2. Past incidents involving vendor drivers (for example, Intel SST driver interactions) underline the importance of vendor-validated drivers.

---

Risk analysis — strengths, weaknesses, and enterprise exposure​

Notable strengths of Microsoft’s approach​

• Rapid public disclosure: Microsoft’s Windows release-health documentation clearly lists the issues, the affected scenarios, and mitigation steps. This transparency helps administrators triage risk quickly.
• Known Issue Rollback (KIR) mechanism: KIR provides a surgical, temporary rollback mechanism for nonsecurity regressions that’s deployable via Group Policy in enterprise environments — a pragmatic tool for preserving uptime while waiting for a permanent fix.

Potential weaknesses and risks​

• Delays in fixes for edge cases: historically, some hardware- or driver-specific issues have taken many months to fully resolve, particularly when the root cause crosses vendor boundaries (OS vs third-party driver). That increases operational risk for organizations that rely on specialized drivers.
• Administrative friction from WUSA regression: many small shops and power users rely on manual .msu installations from a network share. The need to alter SMB behavior or switch distribution channels increases the support burden, especially for decentralized IT environments.
• Arm64 fragmentation: tooling breakage on Arm64 hosts highlights the continued fragility of certain developer and imaging paths on the platform. Organizations standardizing on Arm64 need to validate toolchains carefully.

---

What to watch next (timeline and expected fixes)​

• Microsoft’s public-facing known-issues pages indicate the company is investigating and planning fixes in future cumulative or out-of-band releases. Administrators should monitor the Windows release health dashboard and the Windows 11 update history page for updates and KIR downloads.
• For the EVR/DRM playback regression, Microsoft’s messaging suggests a fix will be issued, potentially in an October cumulative update or via an optional patch depending on severity and reach. Keep an eye on update notes for mentions of EVR/HDCP or DRM corrections.
• If you detect additional regressions in your environment, file detailed reports through the Feedback Hub and coordinate with hardware/software vendors to speed resolution. Microsoft’s public timeline for KIR usage indicates such rollbacks are temporary and removed after a permanent fix is issued, so plan for eventual re-application of the corrected update.

---

Checklist: immediate actions for home users and admins​

• Home users:
• If you use only modern streaming apps: upgrade at convenience.
• If you use legacy media players or external TV capture hardware: postpone 25H2 on production machines and test on a spare device.
• Back up critical data before upgrading.
• Small IT shops:
• Avoid network-share .msu installs while the WUSA issue exists; favor WSUS, Microsoft Update Catalog direct downloads, or rebooting the share to ensure TCP SMB usage.
• Enterprise:
• Run a pilot deployment covering legacy workloads and Arm64 devices.
• Prepare to deploy KIR via Group Policy if you encounter the listed regressions.
• Coordinate with vendors for signed driver updates or patches if hardware-specific regressions appear.

---

Final analysis and verdict​

Windows 11 version 25H2 is a measured update that continues Microsoft’s pattern of incremental, servicing-based feature delivery; the rollout model reduces installation friction. However, the appearance of functionality regressions affecting legacy DRM pipelines, .msu installer workflows over SMB, and Arm64 tooling underscores a persistent reality: even lightweight updates can disrupt specialized workflows and admin processes.
For most consumers the impact will be minimal, but for enterprises and anyone relying on legacy media pipelines or manual update workflows, the prudent course is a staged deployment, focused testing, and readiness to apply Known Issue Rollback policies where necessary. Microsoft’s transparency and the KIR mechanism are strengths in this cycle, but the onus remains on administrators and power users to validate their critical paths before a fleet-wide update.
The immediate takeaway: upgrade carefully, test widely, and prioritize business-critical functionality over calendar-based patching in the short term.

---

Source: Neowin Here are the known issues and bugs in Windows 11 version 25H2