Microsoft has updated its official Release Health page to specify a connection between Windows 11 gaming crashes reported after the cumulative security update "KB5121003" and peripherals or internal PC components that handle RGB lighting. In an update posted at 9:36 PM Pacific Time on August 21, Microsoft explained that when such devices install drivers or code components with names similar to "inpoutx64," they can cause problems when launching certain games.
At the same time, Microsoft outlined a temporary registry-based workaround that prevents the driver in question from loading on the next restart, without deleting it. Previously, only game-specific individual steps were available; now an official workaround targeting systems on Windows 11 24H2/25H2 where the relevant inpoutx64 service key exists has been added.
However, the Release Health status remains "Investigating." Microsoft states it is investigating whether the issue originates from Microsoft's own update, and has not claimed that RGB control software alone causes all the crashes, nor confirmed a definitive causal link with KB5121003.
The RGB and "inpoutx64" clue added on August 21
The triggering update, KB5121003, was released on August 11 for Windows 11 24H2/25H2 clients. Microsoft does not list server products as affected, and the page cites symptoms in "ARC Raiders," "MARVEL Tōkon: Fighting Souls," and "THE FINALS," including games becoming unresponsive, closing without warning, throwing EXCEPTION_ACCESS_VIOLATION errors, or causing the device to restart unexpectedly.
The earlier version of the official page had focused mainly on the fact that Microsoft was investigating the issue, along with the affected games and symptoms. This update specifies the investigation's focus more concretely: certain devices and internal components that support RGB lighting, and the "inpoutx64"-like named components they install. For the first time, Microsoft has officially provided material for tracing symptoms observed in games back to drivers that remain on the PC.
That said, this explanation does not confirm the root cause. Microsoft has not published a list of affected RGB products or utilities, the number of affected devices, or whether all three titles fail through the same mechanism. The name "inpoutx64" alone does not mean every RGB product should be considered part of the problem.
Moreover, the relationship Microsoft has now described is one where problems "can occur when launching certain games." This is not a claim that normal RGB lighting functionality is immediately dangerous; rather, Microsoft is still investigating whether a combination of factors—the specific game, an already-installed driver, and the PC's configuration—is at play.
Start=4 doesn't delete the driver, just stops it from loading at next boot
Microsoft's temporary procedure begins with backing up the registry and recording the current value, then opening HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\inpoutx64 and changing the Start value to 4. A restart is required after the change. In Windows' driver registry settings, Start=0x4 disables the service, representing a state where it will not be loaded.
This operation is not a procedure for uninstalling KB5121003. It is a workaround to prevent the driver being investigated in connection with the issue from loading starting with the next boot, and it does not remove the security changes contained in the update. For users who want to launch the affected games, this offers an option to consider before removing the update.
At the same time, Microsoft has explicitly stated that disabling the driver may make RGB lighting itself, or the software that manages its settings, unusable. This is the reason for recording the Start value before making the change. To revert, Microsoft does not specify a uniform value; instead, it instructs users to restore the original value they recorded. Rather than guessing at a value and rewriting it, this should only be performed on PCs where the backup and recording steps have already been completed.
The registry target is the inpoutx64 service. This is not a procedure that collectively disables similarly named files or other services. Extending the same operation to a PC that lacks the relevant key would not align with the separation of cases that Microsoft's guidance intends.
Microsoft disables it, Embark deletes it
On August 17, Embark Studios, the developer of "THE FINALS," published a separate procedure for users experiencing crashes in that game. It involves stopping and deleting the service, deleting C:\Windows\System32\drivers\inpoutx64.sys, and deleting the registry key as well if necessary, with Embark stating it is working on a long-term fix. In Update 11.6.0 on August 20, Embark also announced that a prompt requesting driver uninstallation may appear while playing.
Both companies address a driver with the same name, but they differ in how easily the change can be reversed and in scope of application. Microsoft's procedure stops the service from loading while leaving room to re-enable it by restoring the original value. Embark's procedure, presented specifically for "THE FINALS," changes the state of the file, the service, and in some cases the registry as well.
| Comparison point | Microsoft's August 21 guidance | Embark's August 17 guidance |
|---|---|---|
| Target | Temporary workaround for systems on Windows 11 24H2/25H2 where the relevant inpoutx64 service key exists |
Countermeasure for crashes in "THE FINALS" |
| Main action | Set Start to 4, preventing the driver from loading after restart |
Delete the service and .sys file, and the registry key if necessary |
| How to revert | Restore the original Start value that was recorded |
No procedure to revert the deleted state is provided in the same guidance |
| Caution | May affect RGB functionality or control software | Guidance specific to this title; applicability to other games has not been confirmed |
As the table shows, Microsoft's guidance cannot be reinterpreted as a general instruction to "delete the file." Conversely, for users who see Embark's prompt in "THE FINALS," simply changing Microsoft's registry setting does not necessarily produce the same result as Embark's deletion procedure. Users need to judge, game by game, which official guidance to follow.
Why an old port-access driver remains on systems
InpOut32/InpOutx64 is a DLL and driver that allows user-level programs to directly access hardware ports. The distributor, Highresolution Enterprises, describes the project as legacy and unsupported, explaining that InpOutx64 was tested up through Windows 10 x64, and while it was expected to work on Windows 11 x64, this was never verified.
As a result, inpoutx64 is not necessarily something installed by the game itself. It may have been left behind by a different utility installed in the past, including software that manages RGB devices. However, since it is not publicly known which products install it or how, this cannot be used to conclusively identify a specific utility as the cause.
Microsoft has not stated that anti-cheat software, specific kernel verification mechanisms, or game protection systems caused this interaction. What can be confirmed at this point is only that Microsoft has found a connection between certain drivers related to RGB-capable devices and the launching of specific games, and has published a workaround that stops the driver from loading.
Until a permanent fix is released, users will need to decide whether to accept the possibility of affecting RGB controls in order to avoid the game-launch issue. Until the Release Health status changes, the affected devices and their sources are specified in more detail, or a permanent fix is released, this workaround—with its accompanying side effect—will remain the standard to go by.