Windows bugs and fixes October 23 2026: status
Chapters
What broke on Windows?
The Windows 11 bug in KB5124010 disrupted applications using Windows’ built-in AC-3 decoder, while Always On VPN connections could remain stuck after an initial failure. BleepingComputer attributes the audio problem to the optional preview update, and gHacks attributes the VPN failure to the September 2026 security updates.
KB5124010 broke Windows AC-3 decoding, BleepingComputer says. According to BleepingComputer, affected applications could fail to launch, close without warning, or work normally until a feature such as playing music was used.
gHacks says the VPN failure affects Windows 11 24H2 and later when automatic selection uses IKEv2 and SSTP and the initial connection attempt fails. Affected connections can remain in a Connecting state or fail to connect, according to gHacks, despite Microsoft previously marking the issue as resolved.
I separate the problems because their current answers differ. The AC-3 failure has a shipped repair. The Always On VPN failure does not.
TL;DR
Windows 11 games and apps relying on Windows' built-in AC-3 decoding could crash after KB5124010, but KB5127648 fixes them, BleepingComputer, published October 19, 2026, says. Always On VPN remains broken after the October updates, and Microsoft plans a later permanent fix, gHacks, published October 23, 2026, says.
- KB5127648 resolves the AC-3 application crashes, BleepingComputer says.
- The October updates did not repair Always On VPN, gHacks says.
- Smart App Control can appear grayed out after KB5127648, Betanews says.
- The VPN workaround removes fallback between IKEv2 and SSTP, gHacks says.
Which Windows fix has shipped?
KB5127648 fixes the AC-3 crash, BleepingComputer says. Microsoft recommends installing the latest security update on affected systems running Windows 11 24H2 and later because the update contains the repair, according to BleepingComputer.
In a report published October 22, Wccftech says KB5127648 repairs AC-3 decoding crashes across Windows 11 24H2, 25H2, and 26H2. Wccftech says KB5127648 was released on October 13 and marks the audio problem as resolved.
Wccftech also attributes a mouse-input stutter repair for certain games and an Explorer-related black-screen repair after sign-in to the same cumulative update. Those repairs do not change the separate Always On VPN status described by gHacks.
I would install KB5127648 on a computer showing the documented AC-3 symptoms. I would not present it as a universal repair for every October Windows problem.
Is Always On VPN fixed?
A permanent Always On VPN fix has not shipped, and Microsoft’s documented mitigation remains the available option, according to gHacks. Microsoft returned the issue to Mitigated after determining that the October updates had not repaired it, gHacks explains.
According to gHacks, the failure follows an unsuccessful initial connection attempt on profiles configured for automatic protocol selection or fallback between IKEv2 and SSTP. The connection can then remain stuck in a Connecting state or fail, even after the October updates are installed, gHacks says.
gHacks says administrators can configure the Always On VPN profile to use a single tunneling protocol, but that workaround removes fallback between IKEv2 and SSTP. The remaining protocol must therefore work on every network used while the mitigation is active, according to gHacks.
Microsoft plans a permanent resolution in an update due in the coming weeks, gHacks says, so I would record the workaround as temporary. I would also test the selected protocol before applying the profile change broadly.
What remains broken after KB5127648?
Smart App Control can appear grayed out after KB5127648, Betanews, published October 20, says. Betanews says devices where Smart App Control is already turned on are not affected, while Microsoft plans a repair for a later update.
Betanews also says a separate USB audio problem from September is only partly repaired, despite the release of emergency update KB5129195. Some USB audio hardware could fail to start or produce no sound after security patches released on September 8, according to Betanews.
KB5129195, issued on September 14, repaired only the 8-channel and 3D audio cases, Betanews says, leaving the wider USB audio problem partly unresolved. That limitation matters because installing KB5129195 does not establish that every affected USB audio device has received a Windows update fix.
I would treat a grayed-out Smart App Control option and continuing USB audio failure as separate problems. Neither should be diagnosed from the AC-3 repair alone.
What can I do today?
Install KB5127648 if the computer has the documented AC-3 crashes, but use the single-protocol mitigation if Always On VPN still fails. Do not assume that the October update repairs the VPN connection merely because it repairs the audio crash.
Betanews advises opening Settings, selecting Windows Update, choosing Check for updates, and restarting if prompted. BleepingComputer says Microsoft recommends the latest security update because it includes the AC-3 repair for affected Windows 11 24H2 and later systems.
Before changing an Always On VPN profile, identify whether IKEv2 or SSTP works on every network the person needs. Record the removed fallback as the workaround’s cost. Restore automatic selection only after a documented permanent repair ships.
For the preceding status, compare my Windows bugs and fixes October 22 2026 report. I would keep Smart App Control and unresolved USB audio cases separate from the AC-3 crash because Betanews documents different fix states for them.