Issue Activating Virtual Camera via Media Foundation Win32 API (HRESULT 0x80070057 - Invalid Parameter) after Windows Update

[Windows 11]

Hello,I am trying to use a virtual camera with Windows Media Foundation API on Windows 11. The camera is correctly detected by MFEnumDeviceSources, but when I try to call ActivateObject(IID_IMFMediaSource, …) on virtual camera, I get the following error:Failed to activate device Virtual Webcam, error: -2147024809 (0x80070057) - Invalid parameter. The camera was working fine until the update two months ago. Problem Details:Virtual camera is correctly detected by MFEnumDeviceSources and returns a valid symbolic link.ActivateObject works on o

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