Microsoft: Windows KB5124010 update crashes some games and apps

Microsoft confirmed that the September 2026 KB5124010 preview update for Windows 11 causes some games and apps using AC-3 (Dolby Digital) audio decoding to crash or fail to launch. The issue mainly affects legacy applications relying on Windows' built-in audio decoder; no fix timeline has been given.

• KB5124010 is an optional update but installs automatically on Windows 11 24H2 with early updates enabled
• Crashes affect games, media players and some productivity apps using AC-3 decoding
• Modern apps with their own audio decoders are not affected
• Microsoft is working on a fix but gave no timeline