The KB5121003 driver block skips enterprise-managed Windows 11 PCs (August 27, 2026)
Chapters
What is new on August 27
The resolution itself is a day old and is covered in the August 26 post, with the original crash reports in the August 16 post. What is new on August 27, 2026 is where the block landed and where it did not.
BleepingComputer, published at 08:16 ET by Sergiu Gatlan, reported the rollout as having started at 6 PM PT on August 26, 2026 with a 24-hour window to reach consumer and business devices, and spelled out what enterprise administrators have to do instead. That last part is the day's real news: a resolution that arrives for home PCs and stops at the edge of a managed fleet.
TL;DR
The driver block that ends the KB5121003 game crashes on Windows 11 reached consumer and business PCs that are not managed by IT, and skipped enterprise-managed devices entirely, according to BleepingComputer on the morning of August 27, 2026. Microsoft's own wording is blunt: "If you have an enterprise-managed device, this resolution will not propagate automatically." On those machines an administrator has to disable the inpoutx64 service by hand, per device, and restart.
- Microsoft: "This resolution is propagating automatically to Windows consumer and business devices that are not managed by IT departments, and a device restart is required."
- The rollout began at 6 PM PT on August 26, 2026 and was expected to reach unmanaged consumer and business devices within 24 hours.
- Managed devices need the registry change: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\inpoutx64, Start set to 4, then a restart.
- Microsoft on that change: "Ongoing investigation does not indicate that disabling this registry key can result in unintended behavior." The block was also to be included in the September 2026 security updates.
- The games are ARC Raiders, MARVEL Tokon: Fighting Souls and The Finals, failing with EXCEPTION_ACCESS_VIOLATION.
Two kinds of device, two different outcomes
As of August 27, 2026 Microsoft's release health entry for Windows 11, version 25H2 (Microsoft Learn) states both halves plainly. The first: "This resolution is propagating automatically to Windows consumer and business devices that are not managed by IT departments, and a device restart is required." The second: "If you have an enterprise-managed device, this resolution will not propagate automatically."
So on an unmanaged PC the sequence is restart, launch the game, see a message window saying the driver was disabled, carry on. In a corporate or education fleet, nothing happens at all. The crashes, the silent exits, the EXCEPTION_ACCESS_VIOLATION errors and the unexpected restarts continue until someone intervenes on each machine.
| Device | How the resolution arrives | Action needed |
|---|---|---|
| Consumer PC not managed by IT | Automatically | Restart |
| Business PC not managed by IT | Automatically | Restart |
| Enterprise-managed device | Not at all | Set Start to 4, then restart |
What Microsoft says about doing it by hand
The manual route is one registry value. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\inpoutx64, set Start to 4, close the editor and restart.
Microsoft's position on the risk is quoted directly: "Ongoing investigation does not indicate that disabling this registry key can result in unintended behavior." It also says it is safe to apply the workaround alongside the block, which matters for a device that picks the block up after someone has already made the change by hand.
The cost is not zero. The peripheral utility that relied on direct port access loses that function, and a fleet-wide registry change plus a reboot is real work with a real change window. There is one piece of good news for the calendar: BleepingComputer reported that the block was to be included in the September 2026 security updates.
Also dated August 27: a preview update and the end of WMIC
Two other items carry the same date on Microsoft's Windows message center (August 27, 2026). The first: "The August 2026 Windows non-security preview update is now available" for Windows 11 versions 26H1, 25H2 and 24H2. Its highlights include a choice of taskbar position, a smaller taskbar option, Start menu sizing, and administrator protection off by default.
The second: "Prepare for the removal of WMIC from Windows 11". Microsoft notes that WMIC has been removed from 24H2 and later and is no longer available as a Feature on Demand. If you have scripts that call wmic, on those builds there is nothing for them to call.
What you can do today
The order I would work in on August 27, 2026:
1. Work out which kind of device you have. If an IT department manages updates on it, the block will not arrive, however long you wait.
2. On an unmanaged PC, restart and launch the game. The rollout began at 6 PM PT on August 26, 2026 with a 24-hour window.
3. On a managed device, open Registry Editor, go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\inpoutx64, note the current Start value, set Start to 4, close the editor and restart.
4. Push it as a managed change rather than one desk at a time, and record the previous Start value so the change can be undone per Microsoft's guidance.
5. Warn the people who own the RGB or fan-control software. The utility loses direct port access, and that is a support call you would otherwise take twice on the same machine.
6. Put September in the plan. The block was to be included in the September 2026 security updates, so a machine that takes that update should not need the manual step afterwards.
If you would rather not touch the registry on every affected machine yourself, Get XLAnt.
Frequently asked questions
How do I know whether my PC counts as enterprise-managed?
If an IT department controls updates on the device, it is managed and the block does not reach it automatically. Microsoft's wording is that the resolution propagates to consumer and business devices that are not managed by IT departments. On a managed device the registry change and a restart are the route.
Is the registry change reversible?
Yes, by restoring the previous Start value, which is why it is worth writing that number down before changing it. Microsoft also says its investigation does not indicate that disabling the key causes unintended behaviour, and that the change is safe to apply alongside the block.